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Show Page HILL TOP TIMES 10 December 3, 1976 Main Chute Hangup crew faces odds, sawiss is a call that starts the Editor's Note: "Main chute hang-up-" now of adrenalin in helicopter crews engaged in mid-ai- r retrieval of remotely piloted vehicles. Capt. Dick Mole's first person account of such a terrifying incident this past summer provides an insight into the professional response of one crew faced with a main chute hang up. As a result of their efforts, an expensive test aircraft was saved to fly again another day. Although as you'll see when you read the article that the fate of the RPV wasn't the only thing in doubt during at least a portion of the recovery. In favor of cutting the cable were the dangers of the ma chute reinflating, the problem of the squealing intercc disrupting normal crew coordination and the fact that on t desert at Dugway Proving Ground, Utah, it was 105F. Even the 7,850 horsepower of our turbine engin was insufficient for the hover needed to guarantee hover is all that is normal undamaged RPV. A we and a for had hover with the Rp required power I HH-53- 's 500-fo- ot j 25-fo- ot 75-fo- ot below us. By Capt. Richard Mole, 6514th Test Squadron " is a cry guaranteed to wipe the smile "Main-chut- e hang-up- ! off any MARS helicopter crewman's face and I wasn't smiling after I heard it at noon on Friday, July 23. r As a new Retrieval System (MARS) helicopter coone of pilot, I was in an upgrade training program two HH-5- 3 helicopters in the Air Force equipped to observe the catch of a remotely piloted vehicle (RPV). Two of the most experienced MARS pilots in the Air Force, Capt. George N. were at the Stokes, pilot and Capt. Robert J. Stroup, ..But alot HH-5- rd co-pil- controls. retrieval is a bit of aviation gymnastics that sees an RPV caught by a heavy-lef- t helicopter traveling at 55 knots as the RPV parachutes down after its flight. The helicopter has grappling hooks which snag the engagement part of the RPV's parachute system and normally cause the system's diameter main parachute to release. After the catch, the RPV is suspended from the helicopter by 390 feet of nylon load-lin- e from the parachute system and 50 to 250 feet of inch steel cable connecting the engagement hooks to the helicopter's winch. The winch is used to raise the RPV to a stow position 15 feet below the helicopter's fuselage. The helicopter then flies to a large foam pad on which the RPV is 100-fo- ot -- set down. ' RPV hangs below helicopter after "catch," with main chute trailing behind it. Small parachute in right side of photo is engagement parachute. (U.S. Air Force Photo by Capt. Richard Mole) suspended below the helicopter tore firmly into the nylon of the engagement - chute; joining helicopter, parachute system and RPV together. came the scream from TSgt. Bill Scrivani standing aft in the helicopter. The RPV's main parachute had failed to release! .."Main-chut- e hang-up!- " high-pitche- d I checked my own and for waited the violent tug that comes when a parachute 100-fodiameter main parachute is linked to a helicopter traveling at 55 knots. Among all the HH-5- 3 pilots in the U.S. Air Force, only Captain Stroup had experienced a main parachute hang-u- p before. That time, the helicopter (an ) was pitched The stress pulled all the violently over to a 60 degree nose-div- e. steel cable from the winch drum. After recovering from the nose-divthe helicopter was landed sateiy. Happily it is an ot ..This particular RPV flight was especially important as it was the second flown by a new type of RPV ) developed to fly electronic countermeasure support for Tactical Air Command fighters. It could be compared to the second flight of a new manned aircraft where the loss of the specially instrumented RPV would delay its operational deployment (AQM-34V- At about $850,000 (for the specially - instrumented test version) the RPV is much cheaper and is built for a different purpose than manned aircraft. In large numbers, Tactical Air Command RPV units will fly the AQM-34to run radar interference for Air Force and Navy fighter bombers against missiles and enemy radar-guide- d guns. Since the RPV is an illusive target, it usually completes its mission and returns home to fly again. Even if a noninstrumented $300,000 RPV is lost to a $250,000 enemy n dollar fighter with crew missile, it will save a and allow the manned aircraft to complete its mission. This is the economics of the RPV test program being conducted at Hill AFB by the 6514th Test Squadron, Air Force Flight Test Center, Air Force Systems Command. Orbiting at the point where the RPV would deploy its recovery parachutes, we flew the largest, most powerful helicopter ever equipped for MARS the HH-5While I watched from my position behind the pilots, skilled technicians worked methodically through checklists to assure that the winch was cocked for the catch. The poles at the rear of the helicopter were properly down and rigged with the grappling hooks that would catch the engagement parachute. Forward in the cargo compartment, John Raccasi, an engineer with Sikorski Aircraft checked the specially mounted s test equipment that would monitor our stresses and we vibrations when caught the 3,300 pound RPV. The final step in preparing the helicopter for mid-ai- r retrieval was when crew donned the their completed parachutes. V anti-aircra- ft 3 I Mid-ai- r ch RPT 500 feet below us and no one was eager to push the button to "kill" the little jet. It was decided to do the best we could to save it without endangering our Mid-Ai- on-boa- of work money and hope had gone into the H-3- e, extremely rare occurrence. Back to the problem at hand: Seconds passed, and nothing happened. I inched to the window and looked down at our reprieve. . . 500 feet below us the RPV was riding normally after the second flight of its life. On the nylon line above it, the main-chut- e flapped wildly, first, partly inflated; then, streaming harmlessly; then, partly inflated again. Next, the harmony of the experienced crew members working together to solve our problem was challenged by a hang-up- , a bad squealing intercom. Like the intercom occurs perhaps once in 1000 flights; it happened this time. main-chut- e I J The plan was to fly as slowly as power would allow, set the RPV on the desert and then sheer the steel cable. It wac ' Captain Stroup's past experience and Captain Stokes' skilled udiius ugainai ui ic ucsci i a suuu uuiiu wiin me idle ui me ie: RPV in the balance: l ii J tv me tirt-sioKes. aescenaea nrv i .was' unini me . . c r ..w captain r r 1 .1 rr iL l if f.n nri v ouu 11 1. me nr ien irorn inai neigni w ui uie uesei luiui could salvage some of the parts. ruei was jettisonea to ria tne HH-5- ot ail unnecessar pods carried below the wings cf weight. But the two the RPV were retained so they might cushion the impact ol . , . i .1 r: r . i i ii lanuing. nnl a iinai cnecK inai an was reauy, apiain iiroui gave a thumbs down to Captain Stokes and we descended thJ final 500 feet. Depth perception from 500 feet is poor at bes! over the smooth white salt flats and TSgt. Scrivani could giv little warning of the RPV's landing until it happened. The helicopter began to lurch over and sink as the RPV act as an anchor. "Cut the cable! Cut the cable!" came over th screeching intercom. Both pilots, MSgt. Johnson and SSgt Beltz pushed the buttons to fire the explosive . the RPV still held us. Mr. Raccasi came from the sidelines anq pushed the mechanical firing pin. There was no release. The cable-cutte- r had failed! Perceiving the problem, Captain Stokes added engine power in an effort to gain the forward airspeed needed to remain airborne. With the pilots nursing airspeed, power and engine temperatures, we staggered forward carrying the RPV minus its two wing pods pulled off by the impact with the sand. .1 . a. i t-- w 1 1 1 1 3 500-poun- 1 1 1 1 d a. 1 cable-cutte- r. .Now the problem of jettisoning the RPV or risking main-chut- e inflation was academic. We could not jettison it and level lights time was running out: the helicopter's fuel-lowere preparing to wink at the pilots. . w multi-millio- - ..Training and experience served us well. TSgt Scrivani took his place by the door shouting over the squealing intercom to the pilots what the treatening main-chutwas e doing. 3. AQM-34V- 's Gerald Johnson aided SSgt. Thomas R. Beltz at the wincn control panel. John Raccasi of Sikorski Aircraft and I stayed clear. Captains Stokes and Stroup were deciding whether to be safe and cut the cable thus destroying the $850,000 test RPV or to keep the RPV attached and try to somehow set it down intact. V f; HH-53'- . - r - - 0 ..Looking over the pilot's shoulder to observe the catch, everything looked normal. The countdown for recovery the sky tuned into an RPV. appraoched zero and a dot-i- o o n drag-chut- e Almost directly above our helicopter, a hign-spee- d into the popped out of the RPV's tail and the craft went seconds A nose-div- e. later of number predetermined expected 100-fomain parachute opened above the the multi-coloreand a descent engagement-chut- e RPV to check its main-chutdeployed on a line above the Now our pilots went to work , scrutinizing the integrity of the to RPV and its parachute system before committing the HH-5. mid-ai- r RPV's with engagement-chutethe Satisfied, contact HH-5- 3 of the nose turned the Stokes Captain In a desperate display of teamwork and dexterity, SSgt. Beltz, TSgt. Scrivani, and Mr. Raccasi worked to reel the steel cable onto the winch drum in the center of the helicopter's cabin. When all the cable was reeled in, it would be possible to cut the nylon line of the RPVs parachute system with a knife. It was imperative for the helicopter's safety that the steel cable be wound correctly on the winch drum in case the main-chut- e reinflated. The steel cable had to be able to wind off the winch drum without jamming. For three or four minutes, the I was in doubt. fate of the AQM-34The only alternative left to our crew would be to cut the cabb with a set of bolt cutters - an operation which would protect the helicopter and its crew, but would take too long when setting the RPV down on the desert. The RPV would be dragged and broken never to fly again. When we were again ready to set it down, a slow rate cf descent was established and the RPV neared the desert. Eager eyes aboard our HH-5- 3 watched the RPV to try to anticipate iU f landing and give the rest of our crew warning. HH-53'- s two in the maximum As the pilots brought power, turbine engines, approached their red line operating temperature. Captain Stokes pulled the nose of the helicopter up and minimum safe airspeed was approached. The RPy touched down softly in the sand and began to slide. Sergcafet f Beltz let out the nylon line that held the RPV to us. and After sliding upright another 75 feet, the HPV stopped slowly leaned over until its left wingtip touched the ground. Its main-chut- e rested close by in the sand j ot d, enroute to some badly needed fuel, ..As our banked sharply over the intact RPV the smiles on our. I faces were those of satisfaction. . . and relief. 24-fo- ot HH-5- e. 3 toward the engagement parachute. it disappeared beneath the helicopter's later seconds Forty 15 feet over it at 55 knots. The hooks flew nose as the helicopter 24-fo- ot Crew of the helicopter who made the flight pose beside r) SSgt. HHtt. MSgt. Johnson, Mr. Hartasi. TSgt. Scrivan, Capt. Mole. ('apt. Stokes. Capt. Stroup it.S. Air Force Photo by Capt. Richard Mole HH-5- 3 "Soaky 17" for a photo. O Was it worth it? Our crew thinks it was. will fly again with only The test AQM-34required for repairs. V ( 16 manhourt I 1 |