ponents in case of battle damage to primary systems, the next location requiring IMC drops might not prove as fortunate. Reliability of a ground system is directly related to the enemy's ability to put it out of commission. The ultimate need for IMC airdrops is a selfcontained aircraft capability requiring no ground aids. Similarly, the ultimate in airland capability under IMC is an aircraft with self-contained precision approach capability. The adverse-weather aerial delivery system (AWADS) development program will equip tactical airlift aircraft with a self-contained avionics package and provide adequate capability with possibly one exception, terrain-avoidance radar. If, in the absence of ground radar, airland had been the only method of resupplying Khe Sanh, the terrain-avoidance capability would have been necessary to provide the pilot glide slope information to complete a safe precision approach. In addition, the need to deliver loads as low as possible is dictated by the inherent inaccuracies of a parachute drop, resulting primarily from unknown wind conditions between the aircraft and ground. Therefore, the lower the aircraft, the more accurate the drop; and to provide the aircraft the capability to descend to these low altitudes for IMC drops, terrain-avoidance radar is essential. It is recognized, however, that because of expense not all tactical airlift aircraft can be equipped with AWADS, even though the need to airland and airdrop in a forward area under instrument conditions will continue to exist. Therefore, a portable instrument landing system (ILS) is required. At Khe Sanh the size of the GCA and TPQ-10 radar, with the necessary location of antenna above ground, proved extremely vulnerable to enemy fire. The current TALAR IV appears to have excellent potential; had it been fully developed and available, its use would most likely have proved extremely effective at Khe Sanh. Light and portable, this miniaturized ILS system could have been placed for airlandings at the end of the runway, completely protected except for an opening for beam coverage. Another transmitter could have been located on the ground at the CARP and used to direct drop aircraft to the release point. Several TALAR units could

have been stocked at Khe Sanh as replacements in case of battle damage or malfunctioning.

• Khe Sanh taught us a valuable lesson concerning the high risk of conventional, fixedwing aircraft performing resupply sorties to a camp surrounded by enemy forces. The most vulnerable aspect of the fixed-wing aircraft's operation is that its approach and departure patterns are necessarily restricted to runway headings, at least for the final portion of the approach and the initial portion of the dewith vertical/short takeoff and landing parture. If tactical airlift had been equipped (v/STOL) aircraft, attempts by the enemy to "zero-in" the approach and departure courses and aircraft damage reduced. As it was, the at Khe Sanh could have been easily thwarted enemy was able to employ small-arms fire effectively, using a minimum number of weapons and personnel to inflict a significant amount of damage. v/STOL aircraft could have used a variety of approaches and landing techArmy helicopters, while delivering, of course, niques, similar to those used by Marine and heavier loads. A v/STOL aircraft could have used the no-stop, low fly-by, dump-truck method of delivery, allowing for deliveries at various locations on Khe Sanh closer to the different supply points. The value of V/STOL to evacuate wounded is easily envisioned; worth considering is the time required for a helicopter flight from Khe Sanh to Dong Ha and then to Da Nang versus that required by V/STOL directly from Khe Sanh to Da Nang or even to Tan Son Nhut, if patients required special attention. Also, with v/STOL, all airbelow GCA-minimum landing conditions, could drops at Khe Sanh, except those performed have been replaced by airlandings.

• The currently programmed light intratheater transport (LIT) is urgently needed for use in an environment like Vietnam. This aircraft should be rugged, capable of operating into extremely short dirt strips, and simple to maintain. Experience in this war has shown that, for the ground forces, it is expensive, in terms of both real estate and defensive ability, to maintain strips longer than 800

1000 feet. The LIT must be built to withstand a Vietnam situation and should be equipped with tires that will not be affected by bullets or shrapnel fragments and fuel tanks made of an explosive-suppression material. In fact, it is vitally important that our present-day aircraft be equipped with such tires and fuel tanks. The programmed LIT is considered the ultimate near-term, light tactical airlift aircraft, scheduled to replace the aging C-123 and the overworked C-7 force. However, it must be acknowledged that there is an urgent need to provide additional STOL aircraft to satisfy the immediate Southeast Asia requirement for specialized airlift. The commitment of additional C-123 aircraft or the procurement of an off-the-shelf, state-of-the-art STOL would enhance the Air Force's ability to sustain the present responsiveness of our tactical airlift force in Vietnam until the advent of the LIT in 1974-75.

• Since integration of new tactical airlift aircraft into the inventory is, unfortunately, still years away, the value and need of the following auxiliary modes of delivery were strongly reaffirmed at Khe Sanh: (1) low-level extraction to deliver heavy, outsized cargo; (2) medium-altitude deliveries as the mainstay of most operations; and (3) high-altitude airdrop techniques to provide the flexibility of delivering cargo under adverse conditions. The availability of these aerial delivery systems allows the airlift commander options from which to select the best aerial delivery mode to support the existing tactical situation, thereby insuring tactical airlift's primary responsibilities of responsiveness and flexibility. The effective performance of GPES, for example, as an option in low-level extraction, proved its merit in the Khe Sanh situation. Another option available during the Khe Sanh operation was an improved LAPES system, with a heavier, 36,000-pound-per-drop capability. This system, although not used at Khe Sanh, was successfully employed in the IV Corps area during that time and was available for other tactical situations if needed. GRADS served as the option in the high-altitude category and could have been used at Khe Sanh

if conditions had worsened. It has, in fact, on occasion since Khe Sanh, proven itself as the only means of supplying an isolated camp when intense enemy fire was too hazardous for helicopters or for low- or medium-level airdrop. Khe Sanh demonstrated, as have numerous other operations throughout Vietnam, that emergency airdropping is often requested under the most varied and unfavorable conditions imaginable. There are other systems of delivery even more exotic than these that could have been effectively used at Khe Sanh, such as a radio-controlled parachute guided to the exact point of impact by the man on the ground. But these are at present extremely expensive, especially for sustained operations such as Khe Sanh, and expense is one of the critical limitations on development today. Therefore, airlanding is always preferred and performed if at all possible, and rightly so. But in Vietnam today, the hazards of landing an airplane, in itself an implied and potential financial risk, are often too great, or even impossible because of the lack of adequate airstrips. Consequently, as long as the present family of aircraft remains the backbone of tactical airlift, we must exert efforts to improve aerial delivery modes -developing cheaper parachutes, a higher degree of accuracy, greater capability and flexibility-instead of eliminating or discounting airdrop because of expense. These methods are vital to our very ability to fulfill emergency requirements of ground units in Vietnam. Future designs of tactical airlift aircraft will, admittedly, decrease the importance of most current airdrop modes, but that day is still years away.

In addition to these broad concepts of airlift developments, other brief and more specific tenets evolved from Khe Sanh which proved significant and worthy of mention and discussion.

-Whenever we establish new or reoccupy old bases away from supply lines, initial consideration must be given to air resupply, not only by airland and helicopter but most particularly by airdrop. Space should be allotted for suitable drop zones inside the defense

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perimeter if possible, convenient to offload points, and usable day or night.

-Prior to the start of any large-scale air operation, air traffic control facilities should be built up immediately to handle all anticipated traffic. At the start of the Khe Sanh operation, there was only one radar approach control (RAPCON) unit, at Hue Phu Bai, to direct the increasing numbers of aircraft into Camp Evans, Quang Tri, Dong Ha, Khe Sanh, and Hue Phu Bai, and it proved inadequate. Subsequently a second unit was located at Quang Tri to handle half of the traffic, thus providing a more effective and safer air traffic control operation.

-The entire Khe Sanh operation graphically illustrated one particular trend of airlift today, the evolution of the specialist. Crews flying in support of Khe Sanh performed daily airdrops that required the versatility of adapting to new techniques or variations of current air resupply standards. Those with thorough knowledge of and practice in the different modes of delivery were naturally more adept. Yet the nature of conditions and the urgency of the situation at Khe Sanh demanded proficiency and accuracy from the start. There was no time for training. The highest possible degree of accuracy and reliability could have been pledged had we been able to press into service a group of select, specialized aircrews, those identified as airdrop experts, highly proficient in LAPES, GPES, CDS, GRADS, heavyequipment drops, and formation flying. With specialists, we could apply a variety of resupply techniques to meet a myriad of contingency and emergency situations for which the standard just doesn't always apply. The crews would be able to adapt immediately to each situation and not need an extensive training program. At Khe Sanh, they would have readily recognized any problems connected with IMC procedures, such as not receiving the threshold mark on time and thereby running the risk of hitting the mountains ahead. Using the radar reflectors along the runway, beacons, and TACAN, they could have determined exactly when they crossed the runway. But again, this comes from experience, from knowing what to look for.