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In these cases friendly artillery fire or air strikes destroyed the
supplies to prevent them from falling into the hands of the enemy.58*

The Americans introduced two more exotic methods in the air resupply of Khe Sanh. These were the Ground Proximity Extraction System (GPES) and the Low Altitude Parachute Extraction System (LAPES), techniques tested by the Air Force just prior to the Vietnam War, but not in general use. With the GPES, loadmasters positioned palletized cargo on rollers inside the aircraft with a hook attached to the pallet in such a manner that it would hang down like the tailhook of a carrier plane. To drop his cargo, the pilot made a low pass over the drop zone trailing the hook and engaged an arresting cable, much like a plane making a carrier landing. The cargo slid out of the back hatch of the aircraft and onto the ground. GPES only had limited use at Khe Sanh, not for any fault with the system, but rather because of faulty installation of the arresting gear. The enemy took the Marines who attempted to install the arresting apparatus under mortar fire forcing them repeatedly to leave their work and take cover. As a result, they failed to anchor it properly. In the first attempt, the Air Force C-130 ripped the arresting cable out of the ground. After the Marines repaired the cable, other efforts were more successful. In one instance, the system extracted from a C-130 a pallet containing 30 dozen eggs, "without a single eggshell being cracked." Another source allowed that two of the eggs were broken.59

LAPES missions, on the other hand, were more numerous, 52 deliveries
as compared to 15 GPES, if not more uneventful. For a LAPES delivery,
the load-masters prepared the cargo in much the same manner as for GPES,
except that, instead of attaching a hook to the pallet, they attached
a parachute. The pilot flew over the runway at an altitude of five feet
and fired a small explosive charge which cut a restraining cable and
allowed the parachute to deploy out of the rear cargo hatch. The parachute
pulled the palletized cargo out of the aircraft to drop the few feet
to the ground. LAPES was extremely accurate, with some crews able to
place their cargo within a 25-meter square. One LAPES delivery malfunctioned,
however, sending a nine-ton pallet careening a quarter of a mile off
the runway at high speed, crashing into a messhall and killing a Marine.
LAPES also caused some damage to the runway, the result of repeated
pounding by nine-ton loads moving at over 100 knots, slamming down from
five feet and skidding along the strip.**

Near the end of February, the Air Force resumed C-130 landings at Khe Sanh. A few days later, on l March, North Vietnamese fire hit and destroyed a C-123 attempting to take off, causing General Momyer to end the experiment and forbid C-130 landings once again. Enemy gunners continued to take a toll, however. On 5 March, they hit a C-123 caught on the ground while changing a flat tire, wrecking the transport completely. Only a day later, 49 died when another C-123 fell to antiaircraft fire while approaching Khe Sanh to land.60

Despite the many problems and risks encountered, both the Air Force and Marine transport aircraft kept the base supplied when they were the only means available to do so. The Air Force aircraft delivered over 12,000 tons of supplies to the garrison, with two thirds of that amount arriving by parachute, LAPES, or GPES. From the period 5 January through 10 April 1968, Marine fixed-wing transports, mostly KC-130s from VMGR-152, hauled 1,904 tons into Khe Sanh and carried 832 passengers.62

While fixed-wing aircraft largely provided for the needs of the units located within the Khe Sanh base itself, the Marines on the isolated hill posts depended upon Marine helicopters for everything from ammunition to water. The 1st Marine Aircraft Wing mounted a monumental helicopter effort using aircraft from both helicopter groups, MAGs-16 and -36. This massive helicopter lift also resulted in new techniques involving close coordination between

* Colonel John F. Mitchell, who commanded the 1st Battalion, 9th Marines
at Khe Sanh, recalled that the drop zone was a "'no-man's land' from
the valley floor west of Khe Sanh and north/northwest of... {the combat
base}." He assigned Company C the recovery mission, supported by Company
A. He recalled that the Marines were frequently subjected to sniper
fire and an occasional ambush. The North Vietnamese often competed in
attempts to recover the supplies, but the Marines seldom lost. Mitchell
believed his Marines recovered about 95 percent of the material dropped
in their zone. Occasionally the dropped material landed in nearby minefields,
which required extreme caution and his men took some casualties as a
result. Col John F. Mitchell, Comments on draft, dtd 5Jan95 (Vietnam
Comment File).

** Colonel Rex O. Dillow, who served as the G-^ or logistics officer
for III MAF, described LAPES as an "experimental U.S. Air Force system,
which was used effectively until all the equipment was torn up. Although
not as efficient as air landed resupply, it was much more efficient
than airdrop due to less dispersion. However, it required a large smooth
surface; the aircraft came in at such a low altitude that they had the
landing gear down in case of an inadvertent touch down. This limited
its use." Col Rex O. Dillow, Comments on draft, dtd 10Nov94 (Vietnam
Comment File).

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