Sam McGowan ‘The TAC-Trained Killer’ at Recife, Brazil on 1 August 1965.
‘As we taxied out to the runway the air was filled with choppers and the tower frequency was filled with instructions. Tower cleared us to take off, so I put the power to max and released the brakes. As we started to roll, a helicopter from the right flew across the runway directly in front of us - idiot. I crammed on the brakes and aborted the takeoff. I put the props into reverse pitch and started backing the airplane up toward the beginning of the runway. Meanwhile loadmaster Steve Hank opened the ramp and told me when we reached the beginning again. With a wary eye out for helicopters we leaped off for Đà Nẵng for fuel. Our troublesome wheel was now leaking brake fluid, but fortunately we had no more shortfield landings ahead. So we just capped off the brake line (leaving three good wheel brakes) and leaped off for Tân Sơn Nhứt feet wet. En route near Phú Cát we listened to an F-4 jock with a crippled airplane punch out near a beach and get picked up by a helicopter.8 All this was getting too much like war for my taste. A rather disquieting day.
Late in 1971 the 374th Tactical Airlift Wing at Tân Sơn Nhứt had assumed direction of ‘Commando Vault’ operations and not surprisingly perhaps, they were extended to include attacks with BLU-82B ‘Big Blues’ on troop and vehicle concentrations in South-East Asia. These accounted for many of the 600 weapons dropped (about two-thirds of which were ‘Big Blues’) in Việtnam, Laos and Cambodia, before the Việtnamese ceasefire in 1973. In the last days of the Việtnam War from 9 to 21 April 1975 South Việtnamese VNAF aircraft dropped BLU-82B bombs on NVA positions in desperation to support ARVN troops in the Battle of Xuân Lộc when the town was captured by the PAVN 4th Army Corps.9 During the Mayaguez10 incident 12-15 May 1975 a MC-130 dropped a single BLU-82B to assist US Marine forces attempting to extract themselves from Koh Tang Island.11
After the C-7 Caribou and C-123 Provider were phased out of service by the USAF, the Hercules units remained the only Air Force tactical transports in southeast Asia and these operated from Thailand during the final months of the war. During 1969-71 massive air transport activity supported US and ARVN incursions into Cambodia and southern Laos. C-130s made ammunition drops to US forces near Ô Rang and Operation ‘Lam Son 719’ was preceded by 250 C-130 sorties lifting an ARVN airborne division and other Việtnamese forces from Saïgon to Đông Hà the capital of Quảng Trị Province and Quảng Trị. Over a seven-week period the Hercules lifted more than 14,000 tons of cargo to a reconstructed logistics base at Khê Sanh (which had been abandoned on 23 June 1968).12
In April and May 1972 the Communist spring offensive resulted in more Air Force supply operations being mounted during to isolated pockets at Kontum in the Central Highlands region which shares borders with Laos and Cambodia and An Lôc, a small provincial capital sixty miles northwest of Saïgon which lies on a plateau surrounded by plantations with tall rubber trees. Major Edward N. Brya (later Brigadier General Brya) designed and tested both the low- and high-level airdrop tactics that relieved the siege of An Lôc. After completing pilot training at Williams AFB, Arizona in May 1962 Brya, who was born in Los Angeles in 1938, was assigned to Dyess AFB, Texas as a C-130 pilot. In January 1965 he transferred to the 35th Troop Carrier Squadron at Naha AB, Okinawa. While there he spent two years flying as an instructor pilot on missions to Southeast Asia, including leaflet drops in North Việtnam. He transitioned to B-52s with an assignment to Carswell AFB, Texas in August 1967. During 1969 and 1970 he rotated with his crew to Guam and the ‘Arc Light’ mission (as the B-52 operations were known) in Southeast Asia. Brya returned to tactical airlift and C-130s in May 1970. He was assigned to Pope AFB, North Carolina, where he served as an instructor, flight commander and wing plans officer. In January 1972 he transferred to Ching Chuan Kang AB, Taiwan, as the wing standardization pilot.
‘In April 1972 as the war in Southeast Asia was winding down the North Việtnamese Army (NVA) launched their spring offensive. This caused a major build up and reinforcement of Air Force, Navy and Marine Air from both the cones and Pacific Theatre. In late 1971 and ’72 we had been withdrawing forces from Southeast Asia. The C-130 wings at Clark, Mactan and Naha had been deactivated and the airplanes returned to the states. The 374th TAW at CCK in Taiwan, with its four squadrons, was the only PACAF asset for C-130 airlift in sea. At the start of the spring offensive the wing had 27 aircraft, 43 crews and 260 maintenance personnel deployed to Việtnam, or incountry as we called it. During April we surged to 44 aircraft, sixty crews and 370 maintenance personnel. In response to the NVA spring offensive our short-field operations increased from the occasional landing at an out of the way field to major operations on a 24 hour basis. Early in April we brought ARVN troops from the 3,000-foot strips in the delta to Biên Hòa for defence of the Saïgon area. Other aircraft went to long-forgotten places to pull out men, land and equipment. We operated in the DMZ and Quảng Tri until the enemy forced us out. The major areas of operation were at Kontum, in the highlands and in the south surrounding Biên Hòa and Saïgon. During April we made 358 short field landings including 51 at night. In the south the centrepiece battle of the spring offensive was fought in Biên Long province. The communists boasted that An Lôc would become the seat of government for the liberated provinces. Colonel Ray Bowers in his excellent air force history of tactical airlift describes the battle for An Lôc as ‘the most trying time of the war for the C-130 crews.’
‘In early April the area was cut off and surrounded by the NVA. The northern half of the town was captured… The Raven13 and their American advisors were forced into a small area in the southeast corner of town. The command element was inside a bunker, which was located by a soccer field 200 metres square. The VNAF had tried without much success to resupply the beleaguered troops; during this time, a C-119 was lost to ground fire. On Saturday, 15th April three C-130s were sent in.14 They used the then approved method of a descending slow down into the DZ. They were briefed by 7th Air Force to approach up the road from the south, as all the VNAF drops had been flown and drop on the soccer field. The first aircraft [commanded by Major Robert Wallace of the 776th TAS, 374th TAW at Ching Chuang Kang AB, Taiwan] made a successful run taking only a couple of hits from ground fire [but released their load]. The second aircraft [62-1787, operating under the call sign ‘Spare 617’ and flown by Captain William Caldwell] came in approximately fifteen minutes later and was under constant fire. One 51 calibre round came through the right hand circuit breaker panel, killed the engineer and went on to shatter the windows on the left side of the cockpit. Other shells ripped the cargo compartment and ignited part of the ammo load. The loadmasters jettisoned the load, which landed on the DZ. Number one and two engines were shut down. The navigator and co-pilot were both wounded and incapacitated. With the loadmasters fighting the fire and manually cranking down the landing gear, the pilot, Captain Bill Caldwell managed to get the aircraft back to Tân Sơn Nhứt. [The third C-130 was unable to drop because of problems with its ramp and door. Though both Wallace and Caldwell dropped in the vicinity of the DZ, none of the cargo from either Hercules was recovered by friendly forces].
Sam McGowan ‘The TAC-Trained Killer’ at Recife, Brazil on 1 August 1965.
Supplies ready for shipment by the ‘Trash Haulers’.
‘Around 10 April I had gone in-county with our wing commander Colonel Andy Iosue. That day we had been out flying a leaflet drop. We returned to Saïgon shortly after Captain Caldwell landed. Colonel Iosue directed me to get with our chief navigator, Major Bob Highly and plan a better way and that the three of us would fly it the next day [16 April]. That night we got together with the airborne FACS and devised some ways, which would hopefully get us through with minimum damage. [The plan called for the C-130s to approach the drop zone at tree-top level at 250 knots, then pop-up to the 600 foot release altitude when about two minutes out]. The FAC would serve as our combat controller. To avoid the appearance of the C-130 from the same heading, we drew a circle around An Lôc and laid out six different inbound tracks into the DZ. The FAC would assess the situation and choose the track which would be the safest for us to enter. He also gave us a recommended outbound track to escape on. We proceeded to an orbit point approximately ten minutes from the Drop Zone. In this orbit at a safe altitude of 5 to 10,000 feet we completed the twenty, ten and six minute checklists. After depressurizing, the bleed valves were closed - this item was not mentioned anywhere in our manuals except for assault landings and takeoffs. We were having a problem with the aft cargo door. The up lock did not always work and thus the door would not stay up. While still in the orbit we opened the door from the back of the airplane and left the aux pump on after the loadmaster completed his checklist. The load was hot, all restraint had been removed and it was being held in only by the CDS gate but if the aircraft were hit and the load needed to be jettisoned. The ramp could be opened and the gate cut.
‘Another new checklist item we instituted was for the pilot and co-pilot to lock their shoulder harness to prevent one of them from falling on the yoke if he was hit. When the FAC cleared the crew into the DZ they would start a Low level dash at approximately 100 feet and 250 knots. Inside two minutes, the slowdown was started. While maintaining the low altitude, the power was reduced to idle. Flaps were lowered on Air speed to the proper CDS setting. At approximately 170 knots the engineer started down the ramp; thirty seconds out, the pilot attained his 600 foot altitude and airspeed in order to identify the drop area. The navigator drew three circles around the DZ, a slowdown, a one minute warning and a release line. The pilot and co-pilot were too busy flying the aircraft to be looking for the DZ. The engineer was watching his panel so the navigator was the only one who could make the drop. Of course during all of this time from two minutes in, the aircraft was under attack from ground fire. As soon as the load was clear the pilot increased airspeed, descended and turned to his escape heading. During the escape manoeuvre, the FAC, who was flying up behind the 130 during the run in, gave directions to help the escape. He would tell you to break left or right as required; then clear you to pop up when out of the threat area. Once out of the area, the crew reviewed the checklist and turned off the green light, which was invariably left on. Unfortunately, we were required to return again and again to the same DZ, at roughly the same altitude and airspeed. Even though we made the drops that day, they had us in their sights and the aircraft were hit.’15
Beginning on Tuesday 18 April the first four C-130s successfully parachuted supplies but each received battle damage. A fifth, C-130E 63-7775 of Detachment 1 in the 374th TAW from Tân Sơn Nhứt flown by Captain Donald B. ‘Doc’ Jensen, which was being used to drop ammunition to South Việtnamese troops was hit west of An Lôc and crash-landed into a swamp near Lai Khê. For several days the detachment at Tân Sơn Nhứt had been trying to drop ammunition and supplies to the defenders of An Lôc, which came under heavy attack from 12 April following the loss of Lộc Ninh seven days earlier. Several attempts were made but most of the loads fell into enemy hands and antiaircraft fire was becoming more ferocious so a change of tactics to low level CDS drops was required. The CDS drops started with a high-speed, low-level approach (250 knots and below 200 feet) until the aircraft climbed rapidly to about 600 feet and slowed to 130 knots for the actual drop. On the 18th as Captain Jensen approached An Lôc at 200 feet to drop its load his C-130 was hit by automatic weapons fire and damaged as it climbed to commence the final run in. The starboard wing caught fire and the load had to be jettisoned but Jensen headed south in the hope of reaching Tân Sơn Nhứt. However, Jensen had to crash-land the aircraft in a swamp near Lai Khê and all the crew were recovered by Army helicopters. (CDS drops were suspended after this incident but later attempted again during the resupply of An Lôc).16
Major Robert W. Kirkpatrick the navigator recalled: ‘As we prepared for the drop, we started taking some sporadic ground fire; nothing very intense at this point, but soon I noticed an orange flash on the horizon, about three miles out. In a voice about 2-3 octaves higher than normal I made the announcement on interphone to the crew: ‘We’re taking fire at 1230 - three miles’, about that time the aircraft made a significant jump with the sound of metal to metal contact, ground fire intensity started to increase drastically at the same time. On the right side of the aircraft we had a big hole, about the size of a basketball and on the right wing the engines spewed fuel and the fire, going well past the tail of the aircraft. About the same time I looked out the left cockpit window and noticed an NVA tank on the ground, with the hatch open, pennants on the antennae and an NVA tank commander standing in the hatch with his pith helmet on looking up at us; I waved at him and he returned the wave. I knew we were on track to the drop zone as the tank’s tube was visually parallel to our track, pointing at An Lôc. After we had dropped our cargo things really started to accelerate for us and the ground fire was extremely intense.
‘We were losing oil from an engine. Then we began losing oil pressure. The pilot tried to shut down the engine and an effort was made to climb and accelerate with the idea of blowing the fire out, none of which worked. The intense ground fire we encountered sounded like a shooting gallery at a carnival; it gradually subsided and the situation with the fire and controlling the aircraft brought up the subject of us bailing out. I knew we were by then over an area where there was a significant concentration of NVA, so my immediate verbal response to the bail-out idea was ‘let’s hold on as long as possible due to the NVA in the area’ (I didn’t feel we would be very welcome guest of the NVA and even if we were, I was not particularly interested in being a guest at the ‘Hànôi Hilton’). Sergeant Bemis continued to scan and report the situation with the fire and condition of the wing from his vantage point in the cargo bay, when all of a sudden he announced in a very calm voice, ‘There goes the wing flap on the right side,’ just very matter of fact, no obvious excitement noted in his voice. When we were getting one problem under control another would come up and we started losing hydraulic pressure, causing the pilots to increasingly focus on the latest problems, which in all likelihood would soon increase in intensity. For the first time the realization that we possibly wouldn’t get out of this came to my mind, however in about the same instant I was able to rationalize that if this was the way it was to be, it would be, but I wasn’t going to give up or just quit trying, so I maintained a can-do attitude and tried to keep the Grim Reaper at a respectable distance.
‘Sergeant Bemis made another announcement, this time that the right aileron was leaving the right wing; the fire seemed to be spreading and globs of metal were rolling off the wing. This must have been about the time an Army helicopter recon team saw our plane and thought we could use some help, as they noticed the fire going past the tail and parts of the aircraft shedding off the wing. We were not aware of their sighting us until later in the day; we were not in any way involved with each other’s activities and they just happened to be in the area and saw us go by.
‘An oxygen bottle exploded, leaving a gaping hole on the right side of the aircraft. Sergeant Bemis reported that white smoke was visible (white smoke in an aircraft fire is not a good thing, it indicates a magnesium fire that won’t go out till it is all consumed) and I was convinced it was time to find a place to set the bird down and quickly.
‘I noticed the pilots were both very busy trying to maintain altitude and directional control. I looked around for a clearing and dead ahead of us was a clearing that appeared level and free of trees. I announced on interphone it was time to land ‘ASAP’ and that we had a clearing just in front of us and I turned and started to strap in my seat, facing forward. Just then, our South Việtnamese Sergeant Kiem came up on the flight deck with a bandage in his hand. He wanted me to help him put it on a neat bullet hole midway between his knee and ankle on his left leg. Since we were about to touch down I said ‘NO’ and motioned for him to get back down the steps to the cargo area.
‘The pilots were beginning to really have some serious control problems since the right wing was melting off as we flew, including the right aileron and flap being gone; flight control hydraulics were also gone, making holding the wings level and aircraft directional control a real challenge.
‘The last thing I remember about the pilots before touchdown was of them expending a lot of effort trying to hold the wings level. The significant aspect of the entire thing was just prior to touch down the right wing started to drop significantly, if the landing aircraft has a wing tip touch down before the rest of the plane, disastrous results can be expected (like a cartwheel and aircraft disintegration). However just prior to touch down, the right wing came level almost simultaneous as we crashed and we were going straight ahead.
‘With rice paddy dykes and craters from artillery or B-52 bombing, the crash landing was not very smooth. As it turned out, we had landed downwind instead of the preferred into the wind but even that turned out to be rather fortunate for us since the aircraft made a180 degree turn with the nose of the aircraft facing into the wind and all the smoke from the aircraft fire was blowing back toward the tail section.
C-130E (63-7811 or 63-9811) gets airborne on a hot sunny day at Đà Nẵng Air Base in Việtnam in 1972. The main landing gear is already almost fully retracted and the nose gear in transit with the nose gear doors still open ... co-pilot hot on the landing gear lever. Getting the landing gear retracted quickly was important on takeoff with heavy loads in order to reduce drag and allow for much improved climb performance. (Robert D. Young)
Again we were lucky because the wind was light and kept the smoke away from where everyone was located in or near the aircraft after the crash landing without fanning the flames, making recovery so much easier.
‘I was strapped in with the seat facing forward. During this short span of time which seemed to be an eternity, I was hanging on to the navigator’s desk with all my might; things were flying all around the cockpit and I was just about to give up trying to hang on when all the motion and noise stopped and a deadly silence settled over the airplane.
‘The airplane was burning, a lot of smoke was in the vicinity but the cockpit appeared to be fairly clear of smoke. I was attempting to untangle myself from radio cables that had wrapped around me and the seat during the crash landing and there was an eerie cry for help coming from the cargo area, ‘Don’t Leave Me’ - it was Sergeant Ralph Bemis, with all sorts of debris on top of him.
‘I was having difficulties with the seatbelt release, it wouldn’t release in the normal fashion, so I got my knife from the pocket on my flight suit and I started cutting seat belt and the radio cords . Just after the crash, I must have been rendered unconscious for a short while as I don’t have any recollection of the pilots departing the flight deck.
‘Fortunately for Sergeant Kiem, the South Việtnamese soldier, he was able to hang on throughout the crash landing about mid way down a 3½ foot ladder that goes between the flight deck and cargo floor level. When the aircraft came to a halt, the nose gear was collapsed and under the aircraft, the crew entrance door had been torn off and all he had to do was step out onto the ground that was level with the lower floor.
‘Captain Jensen, once outside the aircraft, noticed Sergeant Kiem was unable to walk, so he picked him up and carried him away from the aircraft and eventually to one of the rescue Hueys that would pull up in front of the aircraft nose. Captain Jensen later relayed to me his thought was one of the Cobra helicopters may have mistaken Sergeant Kiem for an unfriendly and done him in, so picking him up would take care of that potential problem.
‘During the crash landing, with the wheels hitting soft ground, rice paddy dykes and craters, the aircraft slowed down much faster than it was designed to do; therefore a considerable amount of debris from the back of the cargo bay had come loose, pinning Sergeant Bemis to the floor with a broken arm and ankle. Airman Armstead was free and relatively unhurt and he attempted to dig Sergeant Bemis out of his predicament with no success and found it necessary to exit the cargo area through a large hole in the right side of the aircraft for some fresh air, due to the smoke in the cargo area. He exited and re-entered several times, not wanting to leave his fellow loadmaster. I went down the ladder and immediately saw a pile of twisted metal and an assortment of other aircraft parts all on top of Sergeant Bemis. I made an attempt to clear them, but it seemed to be an impossible task as I couldn’t move anything and started bleeding rather vigorously from cuts on my forearms and hands from the jagged, sharp edges of the various pieces of metal I was trying to remove.
‘After some time in my attempt I decided we would need some outside help in extracting him from his position so I went out of the crew door opening and walked a few steps to about the nose of the aircraft and promptly found myself up to my chin in water. I had stepped into one of the bomb craters that had filled with water and which was covered with thick elephant grass on top. I figured it would be best to just stay there and try to call for help on my SAR (Search and Rescue) radio from that position, keeping a low silhouette in case someone was looking for a large upright target to shoot at.
‘I pulled out my radio to make a ‘Mayday’ call and the antenna fell off and went ‘Plop’ into the water - a bad thing. Next I heard a helicopter approaching from the front of the aircraft - a good thing and I started to climb out of the watery hole. I had just got clear of that when I heard this very loud swishing sound. At first I felt the aircraft was exploding from the fuel fire but it was a rocket being fired by a Cobra gunship overhead. I eventually made it to the Huey that had pulled up near the plane and all the C-130 crew had by now been rescued from the burning aircraft. We had just lifted off when both door gunners started firing their .30 calibre machine guns. Someone had seen fire coming from the tree line, which the door gunners were trying to suppress.
‘Upon arrival at the 3rd Field Hospital in Saïgon we all scrambled out of the Hueys and walked, limped or were carried into the emergency room. Since only Sergeant’s Bemis, Airman Armstead and Sergeant Kiem had wounds requiring immediate attention and hospitalization, the rest of us wandered out of the hospital and found a ride over to Tân Sơn Nhứt. Two days later, my entire body became black and blue from the banging around I received during the crash landing. I still had not had contact with any medical personnel. That was a big mistake.’17
The crash of ‘Doc’ Jensen’s aircraft when the only serious injuries were the loadmasters who were hurt by flying debris in the cargo compartment led to changes, as Edward Brya recalled: ‘We learned to take the unnecessary equipment out: all the seats, stanchions, chains, devices, tool boxes, etc. while we were flying around the country our resourceful crews were acquiring, some defensive equipment. Later on the supply system finally authorized us ballistic helmets, flak vests and some armour-plated vests. However in the early stages of the battle, we were scrounging for equipment anyway we could. Let me tell you about the way the loadmaster went to war. He would put that armoured vest on, take a flak vest apart, tape it around his legs, lay chains on the floor, put the garbage can on the chains, get in and from that position activate the static line retriever as back up for the drop. Next we tried the MLRADS or the mid level radar air drop system, which used ‘Charlie Brown’ reef cutters on the parachutes. We felt we could increase the accuracy of the deliveries by employing the SAC MSQ radar bomb procedures, which the B-52s used for the ‘Arc Light’ mission and the C-130 for the ‘Commando Vault’ mission our BLU 82 10,000lb bomb. The navigator would give a time and ground speed and drift angle to the MSQ site and they in turn could place you within 50 feet of a requested point by means of a GCA. However we still had to compute an accurate carp for use by The MSQ site. The problem as always was the wind so we took readings each thousand feet on the way up. We made the drops from 8,000 feet using the 40 second cutters. A few of the bundles hit the DZ but a majority fell long. We found out later the chutes were opening early due to improper rigging of the cutters.
South Việtnamese refugees at U-Tapao, Thailand.
‘After two days MACV stopped the high drops and directed us to go back low. Down we went. But this time we went at night and we had gunships to help us. The gunship was much better for our purposes than a fighter. He could loiter in the area and deliver continuous fire on a target while we made our run-in. A side note on how we got the gunships - I was over at 7th AF one morning and saw a friend from Pope, Howard Rowland. He was pulling a 30 day TDY from Ubon as the gunship liaison. The rest is history because the crews couldn’t see the obstacles at night. We flew 500 feet above the terrain. We hoped that at night they wouldn’t see us until we were at the target. But of course with a bright moonlit night, they saw you anyway. We had pretty good success putting the bundles on the DZ from low altitude. But once we got in 2 or 3 per night they wanted more. A requirement for ten sorties a night was laid on.
‘During this time Kampong Trach in Cambodia18 came under attack and was surrounded. We ran a drop to the DZ in the daytime and the aircraft sustained 86 hits. The next night we took in three successful sorties. But this same night we lost our second plane at An Lôc. He was hit and downed approximately two clicks southwest of town. The following night the FACS would not clear any more 130s into the An Lôc area. They considered the fire to be murderous. 23 and 37 mm were active; .51-calibre was everywhere. Meanwhile at Kampong Trach the first aircraft in was hit by .51-calibre from a foursided box pattern. The next two airplanes were sent back by the FAC. We had lost any element of surprise. New ground rules were laid down by 7th Air Force. We would have either gunships or fighters for all night drops and fighters for all day drops. Then 7th Air Force directed planning for a ten ship daylight standard level - one minute in trail airdrop to be supported by fire power from A-37s. Colonel Iosue considered this plan suicide [a view shared by the forward air controllers who were working targets around the city] and when he was unable to get MACV to shut it off, somehow he got word to the C-in-C at PACAF and General Clay turned it off. Again the drops were renewed using night low level procedures. However, some day drops were scheduled to make up for those we could not complete at night.
‘In a few more days we lost the third airplane, this time just east of the town. By now the higher echelons of command were convinced of the danger inherent in our mission and we were allowed to go back to high altitude. But due to defences of the enemy such as 37 mm and the new SA-7 Strela-2 missile [Soviet: ‘arrow’; NATO reporting name SA-7 ‘Grail’],19 we were being forced to go to higher altitudes. The SA-7 downed AC-119 gunships over An Lôc and hit a C-130 gunship at 7,500 feet. By this time help was on its way from the States. TAC deployed two 130 squadrons, the 61st from Little Rock and the 36th from Langley. The 61st was an AWADS [All Weather Air Delivery System] squadron, which along with a newly developed high velocity airdrop. Using 1,000lb bundles fitted to 15-foot slotted parachutes provided the needed airdrop accuracy. The successful airdrops turned the tide and by mid-May the NVA had ceased ground attacks on An Lôc. However, Highway 13 from Saïgon remained closed until late June. From mid-April to mid-May C-130 crews made 57 low-level and ninety mid- or high-level drops at An Lôc. During that time at least 56 airplanes were hit plus the five we lost. Seventeen crew members were killed or MIA and another ten wounded. At night, planes who knew they were hit would come back to Saïgon, shut down and discover fuel streaming out of all four main tanks.’
KC-130F BuNo150687 VMGR-152 possibly at MCAS Futema, Okinawa in 1973.
Linking Pleiku with the port cities of the coast was Route 19; ninety miles of winding roadway capable of supporting heavy truck traffic but vulnerable to sabotage or ambush. During early April, clashes along Highway 19 raised concern for security of the important highlands lifeline. On 11 April North Việtnamese elements succeeded in blocking the road at the An Khê Pass near the old American cavalry base. Despite heavy Allied airstrikes the Communists held the roadway closed for sixteen days, requiring that all resupply and reinforcement into the interior by air. On 16 April stocks of fuel in the highlands were down to three days and there simply was not yet enough transport available to sustain the necessary military effort.
The next day three C-130s each fitted with large rubber fuel bladders in the cargo compartment began special POL deliveries into Pleiku. The bladders permitted delivery of 4,500 gallons of fuel per sortie (standard C-130s later delivered POL in cylindrical containers, allowing faster off loading than with the bladder-birds). The dark approaches into the high airhead by the heavily loaded C-130s called for peak flying precision. To avoid ground fire from sectors of Kontum city, crews used overhead circling approaches down to 3,000 feet, avoiding use of landing lights until the last possible moment. Portable lights outlined the location of the runway and fuel could be emptied by pumps carried in the aircraft in fifteen minutes. Three such ‘bladder-bird’ aircraft made twelve trips to Pleiku from Tân Sơn Nhứt and Cam Ranh Bay on the 17th. The effort continued the next day and on the 19th a fourth ship joined the effort - three planes hauled JP-4 and one carried aviation gasoline for reciprocating engines. Other C-130s arrived regularly with hard cargo, interspersed with C-141s temporarily tasked to perform missions inside Việtnam. After offloading at Pleiku, many of the cargo-carriers took aboard passengers - refugees from the battered region headed for safer places. Many were dependents of Việtnamese military men; few carried more than scant possessions. One C-141, flown by Captain Richard Semingson and crew, took off with 394 passengers - the most ever lifted by a Starlifter and more than four times the normal load. Observers on the ground at Tân Sơn Nhứt were amazed at the endless file of humanity streaming from the ship’s tail doors.
The reopening of Highway 19 in late April ended the critical dependence on airlift for transport to Pleiku, but the closure of Highway 14 north of Pleiku on 24 April left the defenders of Kontum wholly isolated except by air during more than two months of heavy and close fighting. Bladder-bird deliveries into Kontum commenced on 23 April, expanding to 24,000 gallons the next day, rebuilding reserves against daily consumption of 15,600. Meanwhile other aircraft landed with hard cargo, departing with the last of the airborne brigade ordered out earlier. Enemy shells periodically interrupted flight-line activity and ground-to-air fire harassed arriving and departing planes. USAF control and aerial port teams worked on the ground at Kontum to speed the flow, as the volume of shelling increased daily.
Hair-raising episodes became commonplace. A bladder-bird received major damage on the 26th. The pilot, Lieutenant Colonel Reed Mulkey of the 50th Tactical Airlift Squadron and a veteran of the 1968 campaign, was attempting departure when a rocket detonated immediately in front of his aircraft, flattening the landing gear, silencing one of the engines and causing major fuel leaks. A three man repair party arrived to inspect the damage and begin repairs. While they worked, more rockets began detonating - one ventilated a C-130 which had just landed and another made a direct hit on a VNAF C-123 parked nearby. US Army and USAF bystanders fought the fire with hand extinguishers, courageously climbing inside and atop the burning hulk. An eleven-man repair team arrived to complete repairs shortly before dusk on 30 April. Working with flashlights and into the morning, the team finished at midday. Rockets continued to detonate, nearly destroying a VNAF C-123 taking off loaded with refugees. Mulkey’s repaired craft and a relief C-130 barely managed take-offs in early afternoon, as both received additional shrapnel holes. Mulkey, with fresh fuel leaks and a lost engine on the previously undamaged side - made a three- engine emergency landing at Pleiku. In a separate episode, Staff Sergeant Floyd J. Monville, a fuels NCO, received acclaim for successfully offloading a damaged C-130 and transferring its bladder system to another C-130, all under fire, using the only vehicle available - a small warehouse type forklift. Monville was later nominated for the Jaycee’s award, ‘America’s Ten Outstanding Young Men of 1972,’ both for his exploits at Kontum and for his role as volunteer director of the Gò Vấp Orphanage in Việtnam.
Altitudes were swiftly increased to above 6,000 feet dropping with ground-radar guidance (GRADS). The drop crews worked with AC-130 gunship crews who provided winds aloft information to the C-130 navigators from their gunsight computers. The results were considerably improved over those attained previously, but ‘high altitude, low-opening’ parachute techniques proved unsuccessful because numerous chutes failed - in part because they had been incorrectly packed by Việtnamese packers. The C-130 crews had no option but to resume the more deadly low-level conventional airdrops; and inevitably the aircraft received hits. Finally, Air Force switched to resupply at night. On the first two nights, the blacked-out C-130 crews enjoyed the element of surprise and managed to get their loads close enough to the target that the South Việtnamese managed to recover most of them. AC-130 gunships provided covering fire. Many if not most of the AC-130 pilots had come from tactical airlift units and were familiar with the airdrop techniques. Light signals used on the ground failed to guide the 130s in and many bundles of supplies missed their mark, some falling into Communist hands. Colonel Andrew Iosue felt that the night landings at Kontum were ‘a dicey operation’ and that the absence of accidents under the conditions was remarkable. Landings ended shortly before dawn on the 25th, with Communist troops lodged at the east end of the runway and delivering small arms fire from three directions at the last C-130 lifting off with the USAF ground teams. Fighting continued throughout the city, with resupply by American and VNAF Chinook helicopters, while the USAF prepared to start C-130 paradrops.
On the third night, 25/26 April, C-130E 64-0508 of Detachment 1, 374th TAW at CCK AB, Taiwan was flown by Major Harry Arlo Amesbury. This crew had dropped supplies to ARVN forces on the 24th at Kompo Trach and their aircraft had been hit by ground fire no less 86 times on that mission. The aircraft approached the drop zone at An Lôc at 500 feet and 170 knots when it entered ‘a wall of fire’ and was hit and crashed shortly afterwards about five miles south of An Lôc. All the crew were killed. Two other Hercules had already been hit by ground fire during the night’s operation and when Major Amesbury’s aircraft was lost the airdrop was brought to a halt for the night.20
On 29 April an SA-7 surface-to-air missile was fired in Quảng Trị, confirming for the first time that the NVA were now equipped with the deadly shoulder-fired missiles. With SA-7s in South Việtnam, low-altitude airdrop missions were almost unthinkable. Fortunately, the Air Force riggers at CCK had come up with a solution to the problem. In World War II and Korea supplies were often dropped without a parachute attached and the USAF riggers discovered that with the proper amount of packing material, bundles containing even ammunition could be safely dropped using slotted extraction parachutes to stabilize, but not retard the descent of the load. The loads descended four times faster than a similar load suspended beneath a G-12 parachute and were thus less susceptible to the winds at altitude. As it turned out the high-velocity drops using the GRADS technique not only allowed the C-130 crews to drop from altitudes above the range of the antiaircraft guns at An Lôc and even the SA-7s (which are effective only to about 4,000 feet), they also allowed unprecedented accuracy. Some supplies such as medical materials and fuel proved unsuitable for the high velocity method and had to be dropped using the HALO parachutes, but most items could be delivered without restraining parachutes. Fortunately, the defenders at An Lôc had discovered a source of fresh water so ammunition and rations were the primary commodities that had to be airdropped to the defenders.
Operation ‘Homecoming’ at Gia Lam Airport in Hànôi in 1973.
The USAF resumed high altitude GRADS daylight drops at An Lôc on 5 May having solved some of the earlier problems with the system and achieved a 90 per cent success rate using this radardirected drop procedure. Loads were attached to parachutes rigged properly and only one of the twenty-four bundles dropped fell into enemy hands.
The high-velocity method was developed just in time, for on 11 May the first SA-7 firings were reported at An Lôc. The drop planes were able to operate without fear of the Strela missiles, but the AC-130 gunships were considerably affected. Their guns lost their effectiveness at the 10,000 foot altitudes that were necessary to avoid the SA-7s. Tactics were worked out for the AC-130 and C-130 crews to fire decoy flares when an SA-7 firing was observed. The heat-seeking missiles would home on the more intense heat of the flares instead of the C-130’s exhaust. Four C-130 crews reported SA-7 firings in South Việtnam in May/June but none were hit. The AC-130s did not fare as well; one was badly damaged on 12 May and another was shot down near Huế in June.
Because only a portion of the C-130 crews at CCK were drop qualified, the missions over An Lôc meant that the same people were bearing the brunt of the burden. The crews were well aware that each mission might be their last. They wore flak suits and helmets while the loadmasters filled the airplane garbage can with tie-down chains and climbed inside it while over the drop zone. For a week the night drops continued, with the C-130 crews encountering heavy fire on each mission and only about 10% of the loads were positively recovered. More than half of the drop planes took hits and several crewmembers were wounded. Two daylight supply operations and one night drop to 20,000 defenders and refugees at An Lôc had cost three C-130s by 3 May and on the night of 2/3 May the C-130s failed to make a single successful delivery. The following night, C-130E 62-1797 of Detachment 1in the 374th TAW from Tân Sơn Nhứt was shot down. Captain Donald Lee Unger had made his low level CDS drop and was pulling up from 500 feet to return to Tân Sơn Nhứt when his aircraft was hit by automatic weapons fire. The Hercules crashed a few miles from An Lôc and all the crew were killed. After this incident no more low level drops were made at An Lôc.
As from 8 May, when the An Lôc garrison recovered 65 of the 88 tons dropped, things improved and by the end of the siege, on 18 June, 7,600 tons had been dropped by the C-130s in more than 600 sorties.
Meanwhile, Kontum had been cut off when the NVA captured Đắk Tô on 24 April and cut the road from Pleiku. From then on the only method of resupply of fuel, food, ammunition and other supplies was by air. During the eight days prior to 3 May, the C-130s made approximately fifteen landings daily at Kontum - a typical day’s work was seven loads of munitions, five of POL and three of rice. During the same eight days VNAF transports made fifteen deliveries. On 2 May, a C-130 lost several feet of wingtip in a collision with a helicopter at the crowded airhead, but managed an emergency landing at Pleiku. Rocket damage to another C-130 the next day brought a decision to shift to night operations. Meanwhile, rocket attacks were beginning at Pleiku, threatening both C-130s on the ground there. Day operations to Kontum ceased abruptly on 17 May after enemy fire damaged several C-130s, burned two VNAF C-123s and destroyed a C-130E (63-7798) in the 776th TAS 374th TAW; the latter was hit in one of its engines by a mortar or a rocket while taking off. Captain Richard Harold Hagman and three other crewmen were killed. The lone survivor was rescued by an American helicopter. Hercules operations resumed exclusively at night on 18/19 May, with seventeen C-130s running the gauntlet of enemy fire to carry out successful deliveries and fifteen more on the 20th sustained the flow of supplies. Resupply continued nightly under cover of allied gunships. On the night of 22/23 May two C-130s received shrapnel damage, one managing an emergency landing at Đà Nẵng. C-130E 62-1854 Quan Loi Queen of ‘E’ Flight, 21st Tactical Airlift Squadron, damaged after midnight on 22 May, was further damaged and the next day when it delayed its departure past dawn and was destroyed by a missile on the ground. Two days later the Communists seized a part of the Kontum runway, closing the airfield to landings except by helicopters and it was not until the 28th that the Hercules could resume airdrops overhead. More than 2,000 tons were dropped in 130 C-130 sorties before the Hercules could resume night landings on 8 June.
An important forerunner of the Kontum airdrops were the drops begun in mid-May at several isolated and hard-pressed camps farther north and west. Dak Pek, Mang Buk and Ben Het received a total of 19 C-130 drops during May using techniques developed recently for release from altitudes above the level of anti-aircraft effectiveness. Drops began at Kontum with a single mission on the afternoon of 27 May. During the next four days, 19 C-130 loads were parachuted to a drop zone near the city’s south-west corner (the Communists held much of the east half of the city). With some success in pushing the Communists from their sectors, the drop zone was shifted to the more convenient north-west sector; 68 C-130 drop sorties took place during the first seven days of June. Although retrieval parties on the ground had trouble keeping up with the volume of deliveries, the II Corps G-4 reported that the drops ‘have been very accurate and nearly all parachute bundles are impacting in the recovery area.’ Much of this success reflected the painful evolution of effective methods experienced earlier at An Lôc. C-130 landings resumed on the night of 8/9 June. Six 130s made blacked-out GCA approaches and landings that night. During C-130 approaches, friendly artillery fire was directed into the likely danger area to discourage enemy shelling and flare shells were detonated near the runway in hopes of distracting any surface-to-air missile. The daytime drops continued, ending on 14 June after another 48 sorties since the 7th. Through the nineteen days of drops, not a single C-130 received battle damage.
Stretcher cases being airlifted from Việtnam in a RAAF C-130. (Australian War Memorial)
Australian troops leaving Việtnam in C-130E A97-189 (65-12906).
A further aspect gave added significance to the Kontum resupply. Sixteen of the drops were performed using the All Weather Air Delivery System (AWADS) by aircraft and crews recently deployed under ‘Constant Guard IV’ from the United States. A preliminary mission on 1 June attained moderate success at Svay Rieng in Cambodia. Two days later, two aircraft released at Kontum, aiming with the aid of a ground radar beacon transponder. Accuracy appeared satisfactory, but half the bundles could not be recovered because of enemy fire on the drop zone. During 7-14 June C-130 crews made another fifteen AWADS drops at Kontum. Navigators aimed using the self-contained radar and computer system, now using reflected radar returns. A bridge south of the town served for late computer update; a river bend at the city served as the final offset aiming point. The largest recorded impact error was 300 metres; all drops were from 10,000 feet. One drop, on 12 June, was performed in two-ship formation using the electronic station-keeping equipment (SKE), the trail ship dropping 5.4 seconds behind the AWADS-equipped leader. The result was spectacular; the second ship’s load landed atop the leader’s. The only significant problems in SKE appeared to be the trail ship’s difficulty in flying in the leader’s turbulent wake while heavy and slow.
From July 1965-November 1972 the Hercules flew no fewer than 708,087 sorties in Việtnam, with peak monthly operations being recorded in May 1968 when in-country Hercules flew 14,392 sorties.
US bombing of North Việtnam had resumed with a vengeance on 10 May 1972 with ‘Linebacker I’ raids aimed at the enemy’s road and rail system to prevent supplies reaching the Communists operating in South Việtnam. ‘Linebacker II’ operations began on 18 December 1972 and lasted until the 29th. These were the most effective strikes against enemy defences in the whole war and they ultimately persuaded the Hànôi government to seek an end to hostilities and to conclude a peace treaty. Negotiations in Paris ended with the signing of a peace agreement on 23 January 1973 and all air operations ceased four days later; this brought to an end one of the most horrific wars in history. In its course 58,022 Americans died and it brought America it worldwide condemnation for its role in South-East Asia. A total of 126 tactical airlift aircraft were lost during the war, fifty-five of them Hercules.
‘Grunts’ of the US 3rd Marine Division embarking on KC-130F transport/tanker BuNo150687 of VMGR-152 at MCAS Futema, Okinawa en route home to the US late in 1974. (S/Sgt Mennillo USMC).
Although all US ground forces were withdrawn from South Việtnam, air-raids into neighbouring Cambodia and Laos continued until August 1973. In the spring of 1973 the C-130s switched their full attention to the airlift of supplies to Cambodia, with the last war-related sorties being undertaken in 1975 by an aircraft flown by civilian crews of Birdair Inc., a contract operator to which the USAF gave equipment and technical assistance. Then both Cambodia and Laos fell to the Communists and early in 1975 the North turned its attentions to the final take-over of South Việtnam. Inevitably the South, now without US military support, collapsed under the full might of the Communists’ spring offensive. Indeed the onslaught was so rapid and so intensive that by March, the original ‘Talon Vise’ contingency plan to evacuate US dependents and non-essential personnel was abandoned and beginning on 1 April ‘Frequent Wind’ began the wholesale evacuation of all US forces left in Việtnam.
C-130s of Tactical Airlift Command joined C-141As and C-5A Galaxies of the Military Airlift Command (MAC) in a mass exodus of US and Việtnamese military and civilians fleeing South Việtnam before the country was completely overwhelmed. (C-5 flights were withdrawn following a tragic crash of a Galaxy on 4 April, which claimed 155 lives.) After 20 April the situation became even more critical and safe operating loads were ignored so that transports could take off from Saïgon, now completely surrounded by Communist troops, in grossly overloaded condition. C-130s departed carrying between 180 and even 260 evacuees on board, while a VNAF C-130 is reported to have fled loaded with 452 people. By 27 April the danger from Communist small arms, Triple-A and shoulder- fired ground-to-air missiles had become too great for most aircraft and all C-141A flights were suspended. The Hercules, however, carried on, flying right around the clock until the early hours of 29 April when heavy and accurate Communist rocket fire at Tân Sơn Nhứt forced even these to cease operations.
Việtnamese refugees being evacuated in April 1973.
From 1-29 April 1975 a total of 50,493 people had been airlifted during the course of 375 C-130, C-141 and other aircraft sorties. On 12 April the US Embassy in Saïgon was evacuated and 287 staff were flown to US carriers offshore. The last US military C-130 loss was the 314th Tactical Airlift Wing C-130E 72-1297, hit by advancing NVA rocket fire on 28 April, forcing Tân Sơn Nhứt Air Base to close to fixed wing evacuation of the collapsing South Việtnamese capital of Saïgon. On 29 April 900 Americans were airlifted by the US Navy to five carriers. Next day, Saïgon was in Communist hands and the South was under control of North Việtnam. Six C-130s were among the ninety aircraft flown out of the country to Thailand by VNAF personnel, but about 1,100 aircraft, including twenty-three C-130As in the 435th and 437th Squadrons, fell into Communist hands before the ink was dry on the surrender document issued to the Republic of Việtnam’s President Dương Văn Minh.
1 This incident was undoubtedly the worst air disaster of the war until the loss of a C-5A near Saigon on 4 April 1975. Vietnam Air Losses by Chris Hobson (Midland Publishing 2001).
2 Joe M Jackson and Major Jesse W. Campbell of the 311th ACS landed the Provider which was fired at continuously until it took off with the three men safely on board. Lieutenant Colonel Jackson received the Medal of Honor for this feat of skill and courage under fire.
3 A Trash Hauler in Vietnam; Memoir of Four Tactical Airlift Tours, 1965-1968.
4 1st Lieutenant Ragland had been shot down over Korea in November 1951by a Soviet Ace pilot, Colonel Yevgeny Pepelyayev in his MiG-15, forcing Ragland to bail out of his F-86E. Prior to his shoot down, Ragland had shot down a Soviet MiG flown by Lieutenant Alfey Dostoievsky and he and Lieutenant Kenneth Chandler had performed an audacious strike against North Korean airbase of Uiju ten days earlier, on 18 November, destroying four MiGs on the ground). He was a PoW in the Pyok-Dong prison camp for two years.
5 John Gargus was awarded the Silver Star. In part, his citation said: ‘In the face of heavy enemy anti-aircraft artillery and surface-to-air missile fire, Major Gargus skilfully managed all navigational systems and equipment to insure precise navigation and accurate timing on target which were essential for completion of this dangerous mission. As a result of Major Gargus’ heroic efforts, the force arrived at Sơn Tây without incident, the enemy ground forces were completely surprised and the mission was successfully completed.’
6 US intelligence may have identified this the day before the raid, but the raid was sent anyway. Three commando teams landed at the camp: The first team intentionally crash landed a helicopter right in the middle of the camp to get into position as quickly as possible. The second landed 400 metres away by accident, at what turned out to be a base for Russian and Chinese military advisers. The team attacked the headquarters and killed an estimated more than 100 people at the base. The third team landed outside the main complex and assisted in securing the facility. The raid succeeded completely at its technical objective of seizing control of the camp. There were no prisoners present to rescue, though 26 minutes after the first helicopter intentionally crash landed all US commandoes were recovered and flying home. One US soldier was wounded in the leg and one broke his ankle in the intentional crash landing. An unknown number of North Việtnamese soldiers were killed in the raid. The unsuccessful mission did bring an ironic success for Simons and his troops. The attempt to rescue prisoners brought the world’s attention to the inhumane treatment of the American PoWs. The raid on Sơn Tây altered how the North Việtnamese housed, treated and interacted with the foreign prisoners. Some have questioned whether the real intention of the raid was dual purpose and in addition to the attempted rescues of PoWs was designed to send a message to the Russians and the Chinese assisting the Việtnamese.
7 Caribou C-7B 62-4161 of the 459 TAS, 483 TAW at Phú Cat was approaching the Đức Phổ Special Forces camp, about 20 miles south of Quảng Ngai on 3 August 1967 when it was hit by a shell from a US Army 155mm howitzer. The aircraft had flown into the line of fire and the shell blew off its entire rear fuselage and tail section. Captains Alan Eugene Hendrickson and John Dudley Wiley and Tech Sergeant Zane Aubry Carter were killed.
8 F-4D 65-0637 in the 12th TFW at Phủ Cát crewed by Captain Hedditch and 1st Lieutenant T. McLaughlin was taking part in a ‘Steel Tiger’ night mission in southern Laos. Hedditch was making his third pass on a target near Ban Tampanko [in Savannakhet Province, Laos] when his aircraft was struck by ground fire. Both crew ejected successfully and were rescued by a USAF helicopter. Vietnam Air Losses by Chris Hobson (Midland Publishing 2001).
9 Once Xuân Lộc fell on 21 April 1975, the PVN battled with the last remaining elements of III Corp Armoured Task Force, remnants of the 18th Infantry Division and depleted ARVN Marine, Airborne and Ranger Battalions in a fighting retreat that lasted nine days, until they reached Sàigòn and PVN armoured columns crashed throughout the gates of South Việtnam’s Presidential Palace on 30 April 1975, effectively ending the war.
10 The merchant ship’s crew, whose seizure at sea had prompted the US attack, had been released in good health, unknown to the US Marines or the US command of the operation before they attacked. Nevertheless, the Marines boarded and recaptured the ship anchored offshore a Cambodian island, finding it empty. It was the only known engagement between US ground forces and the Khmer Rouge.
11 The incident took place between the Kingdom of Cambodia and the US less than a month after the Khmer Rouge took control of the capital Phnom Penh ousting the US backed Khmer Republic. It was the last official battle of the Việtnam War. The names of the Americans killed, as well as those of three US Marines who were left behind on the island of Koh Tang after the battle and were subsequently executed by the Khmer Rouge, are the last names on the Việtnam Veterans Memorial.
12 On 19 June 1968 Operation ‘Charlie’, the final evacuation and destruction of the Khê Sanh Combat Base began. The Marines withdrew all salvageable material and destroyed everything else. The NVA continued shelling the base and on 1 July launched a company-sized infantry attack against its perimeter. On 9 July the flag of the Việt Công was set up at Ta Con (Khê Sanh) airfield. On 13 July Hồ Chi Minh sent a message to the soldiers of the Route 9 - Khê Sanh Front affirming their victory at Khê Sanh. It was the first time in the war that the Americans abandoned a major combat base because of enemy pressure.
13 The ‘Raven’ Forward Air Controllers, also known as ‘The Ravens’, were fighter pilots used for forward air control in a covert operation in conjunction with the Central Intelligence Agency in Laos. The Ravens provided direction for most of the air strikes against communist Pathet Lao targets and People’s Army of Việtnam’s infiltrators in support of the Laotian Hmong guerrilla army.
14 On the night of 14 April three 374th crews were briefed for airdrop missions over An Lôc the next morning. After an initial mission delay, the three C-130Es took off from Tân Sơn Nhầt for the short flight to An Lôc. The first crew over the DZ, took hits. The second crew elected to approach the drop zone from a different direction.
15 Although the two C-130 crews, including one with Iosue, Brya and Highley, thought they identified the drop zone, it turned out that they had been given the wrong coordinates and the loads were not recovered.
16 Vietnam Air Losses by Chris Hobson (Midland Publishing 2001).
17 ‘Sp4 Shearer was the Huey crew member that had the job of getting out of the Huey to make a close up visual of the wreckage. I found out much later that he was positive he would find a group of mangled bodies in the wreckage and not knowing the fate of the survivors was something that was to haunt him for 32 years, which is when we met at the coffee shop of Luke Air Force Base, Arizona, in 2004.’
18 One of the eight districts of the Kampot Province, at the eastern part bordering Việtnam to the east, Banteay Meas District to the north, Kep Province to the west and the Gulf of Thailand to the south.
19 The Strela-2 system along with the more advanced Strela-2M it achieved 204 hits out of 589 firings against US aircraft between 1972 and 1975 according to Russian sources.
20 See Vietnam Air Losses by Chris Hobson (Midland Publishing 2001).