Can you survive a bailout at Mach 3+ from 78,000' ?

Discussion in 'The Okie Corral' started by HKMark23, Sep 3, 2005.

  1. HKMark23

    HKMark23 Millennium Member

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    Dec 17, 1999
    Chez Bippy
    By Bill Weaver

    Among professional aviators, there's a well-worn saying: Flying is
    simply hours of boredom punctuated by moments of stark terror. And
    yet, I don't recall too many periods of boredom during my 30-year
    career with Lockheed, most of which was spent as a test pilot.

    By far, the most memorable flight occurred on Jan. 25, 1966. Jim
    Zwayer, a Lockheed flight test reconnaissance and navigation systems
    specialist, and I were evaluating those systems on an SR-71 Blackbird
    test from Edwards AFB, Calif. We also were investigating procedures
    designed to reduce trim drag and improve high-Mach cruise
    performance. The latter involved flying with the center-of-gravity
    (CG) located further aft than normal, which reduced the Blackbird's
    longitudinal stability.

    We took off from Edwards at 11:20 a.m. and completed the mission's
    first leg without incident. After refueling from a KC-135 tanker, we
    turned eastbound, accelerated to a Mach 3.2-cruise speed and climbed
    to 78,000 ft., our initial cruise-climb altitude.

    Several minutes into cruise, the right engine inlet's automatic
    control system malfunctioned, requiring a switch to manual control.
    The SR-71's inlet configuration was automatically adjusted during
    supersonic flight to decelerate air flow in the duct, slowing it to
    subsonic speed before reaching the engine's face. This was
    accomplished by the inlet's center-body spike translating aft, and by
    modulating the inlet's forward bypass doors. Normally, these actions
    were scheduled automatically as a function of Mach number,
    positioning the normal shock wave (where air flow becomes subsonic)
    inside the inlet to ensure optimum engine performance.

    Without proper scheduling, disturbances inside the inlet could result
    in the shock wave being expelled forward--a phenomenon known as an
    "inlet unstart." That causes an instantaneous loss of engine thrust,
    explosive banging noises and violent yawing of the aircraft--like
    being in a train wreck. Unstarts were not uncommon at that time in
    the SR-71's development, but a properly functioning system would
    recapture the shock wave and restore normal operation.

    On the planned test profile, we entered a programmed 35-deg. bank
    turn to the right. An immediate unstart occurred on the right engine,
    forcing the aircraft to roll further right and start to pitch up. I
    jammed the control stick as far left and forward as it would go. No
    response. I instantly knew we were in for a wild ride.

    I attempted to tell Jim what was happening and to stay with the
    airplane until we reached a lower speed and altitude. I didn't think
    the chances of surviving an ejection at Mach 3.18 and 78,800 ft. were
    very good. However, g-forces built up so rapidly that my words came
    out garbled and unintelligible, as confirmed later by the cockpit
    voice recorder.

    The cumulative effects of system malfunctions, reduced longitudinal
    stability, increased angle-of-attack in the turn, supersonic speed,
    high altitude and other factors imposed forces on the airframe that
    exceeded flight control authority and the Stability Augmentation
    System's ability to restore control.

    Everything seemed to unfold in slow motion. I learned later the time
    from event onset to catastrophic departure from controlled flight was
    only 2-3 sec. Still trying to communicate with Jim, I blacked out,
    succumbing to extremely high g-forces. The SR-71 then literally
    disintegrated around us.

    From that point, I was just along for the ride.

    My next recollection was a hazy thought that I was having a bad
    dream. Maybe I'll wake up and get out of this mess, I mused.
    Gradually regaining consciousness, I realized this was no dream; it
    had really happened. That also was disturbing, because I could not
    have survived what had just happened. Therefore, I must be dead.
    Since I didn't feel bad--just a detached sense of euphoria--I decided
    being dead wasn't so bad after all.

    AS FULL AWARENESS took hold, I realized I was not dead, but had
    somehow separated from the airplane. I had no idea how this could
    have happened; I hadn't initiated an ejection. The sound of rushing
    air and what sounded like straps flapping in the wind confirmed I was
    falling, but I couldn't see anything. My pressure suit's face plate
    had frozen over and I was staring at a layer of ice.

    The pressure suit was inflated, so I knew an emergency oxygen
    cylinder in the seat kit attached to my parachute harness was
    functioning. It not only supplied breathing oxygen, but also
    pressurized the suit, preventing my blood from boiling at extremely
    high altitudes. I didn't appreciate it at the time, but the suit's
    pressurization had also provided physical protection from intense
    buffeting and g-forces. That inflated suit had become my own escape

    My next concern was about stability and tumbling. Air density at high
    altitude is insufficient to resist a body's tumbling motions, and
    centrifugal forces high enough to cause physical injury could develop
    quickly. For that reason, the SR-71's parachute system was designed
    to automatically deploy a small-diameter stabilizing chute shortly
    after ejection and seat separation. Since I had not intentionally
    activated the ejection system--and assuming all automatic functions
    depended on a proper ejection sequence--it occurred to me the
    stabilizing chute may not have deployed.

    However, I quickly determined I was falling vertically and not
    tumbling. The little chute must have deployed and was doing its job.
    Next concern: the main parachute, which was designed to open
    automatically at 15,000 ft. Again, I had no assurance the
    automatic-opening function would work.

    I couldn't ascertain my altitude because I still couldn't see through
    the iced-up face plate. There was no way to know how long I had been
    blacked-out, or how far I had fallen. I felt for the
    manual-activation D-ring on my chute harness, but with the suit
    inflated and my hands numbed by cold, I couldn't locate it. I decided
    I'd better open the face plate, try to estimate my height above the
    ground, then locate that "D" ring. Just as I reached for the face
    plate, I felt the reassuring sudden deceleration of main-chute

    I raised the frozen face plate and discovered its uplatch was broken.
    Using one hand to hold that plate up, I saw I was descending through
    a clear, winter sky with unlimited visibility. I was greatly relieved
    to see Jim's parachute coming down about a quarter of a mile away. I
    didn't think either of us could have survived the aircraft's breakup,
    so seeing Jim had also escaped lifted my spirits incredibly.

    I could also see burning wreckage on the ground a few miles from
    where we would land. The terrain didn't look at all inviting--a
    desolate, high plateau dotted with patches of snow and no signs of
  2. HKMark23

    HKMark23 Millennium Member

    Likes Received:
    Dec 17, 1999
    Chez Bippy
    I tried to rotate the parachute and look in other directions. But
    with one hand devoted to keeping the face plate up and both hands
    numb from high-altitude, subfreezing temperatures, I couldn't
    manipulate the risers enough to turn. Before the breakup, we'd
    started a turn in the New Mexico-Colorado-Oklahoma-Texas border
    region. The SR-71 had a turning radius of about 100 mi. at that speed
    and altitude, so I wasn't even sure what state we were going to land
    in. But, because it was about 3:00 p.m., I was certain we would be
    spending the night out here.

    At about 300 ft. above the ground, I yanked the seat kit's release
    handle and made sure it was still tied to me by a long lanyard.
    Releasing the hea vy kit ensured I wouldn't land with it attached to
    my derriere, which could break a leg or cause other injuries. I then
    tried to recall what survival items were in that kit, as well as
    techniques I had been taught in survival training.

    Looking down, I was startled to see a fairly large animal--perhaps an
    antelope--directly under me. Evidently, it was just as startled as I
    was because it literally took off in a cloud of dust.

    My first-ever parachute landing was pretty smooth. I landed on fairly
    soft ground, managing to avoid rocks, cacti and antelopes. My chute
    was still billowing in the wind, though. I struggled to collapse it
    with one hand, holding the still-frozen face plate up with the other.

    "Can I help you?" a voice said.

    Was I hearing things? I must be hallucinating. Then I looked up and
    saw a guy walking toward me, wearing a cowboy hat. A helicopter was
    idling a short distance behind him. If I had been at Edwards and told
    the search-and-rescue unit that I was going to bail out over the
    Rogers Dry Lake at a particular time of day, a crew couldn't have
    gotten to me as fast as that cowboy-pilot had.

    The gentleman was Albert Mitchell, Jr., owner of a huge cattle ranch
    in northeastern New Mexico. I had landed about 1.5 mi. from his ranch
    house--and from a hangar for his two-place Hughes helicopter. Amazed
    to see him, I replied I was having a little trouble with my chute. He
    walked over and collapsed the canopy, anchoring it with several
    rocks. He had seen Jim and me floating down and had radioed the New
    Mexico Highway Patrol, the Air Force and the nearest hospital.

    Extracting myself from the parachute harness, I discovered the source
    of those flapping-strap noises heard on the way down. My seat belt
    and shoulder harness were still draped around me, attached and
    latched. The lap belt had been shredded on each side of my hips,
    where the straps had fed through knurled adjustment rollers. The
    shoulder harness had shredded in a similar manner across my back. The
    ejection seat had never left the airplane; I had been ripped out of
    it by the extreme forces, seat belt and shoulder harness still

    I also noted that one of the two lines that supplied oxygen to my
    pressure suit had come loose, and the other was barely hanging on. If
    that second line had become detached at high altitude, the deflated
    pressure suit wouldn't have provided any protection. I knew an oxygen
    supply was critical for breathing and suit-pressurization, but didn't
    appreciate how much physical protection an inflated pressure suit
    could provide. That the suit could withstand forces sufficient to
    disintegrate an airplane and shred heavy nylon seat belts, yet leave
    me with only a few bruises and minor whiplash was impressive. I truly
    appreciated having my own little escape capsule.

    After helping me with the chute, Mitchell said he'd check on Jim. He
    climbed into his helicopter, flew a short distance away and returned
    about 10 min. later with devastating news: Jim was dead. Apparently,
    he had suffered a broken neck during the aircraft's disintegration
    and was killed instantly. Mitchell said his ranch foreman would soon
    arrive to watch over Jim's body until the authorities arrived.

    I asked to see Jim and, after verifying there was nothing more that
    could be done, agreed to let Mitchell fly me to the Tucumcari
    hospital, about 60 mi. to the south.

    I have vivid memories of that helicopter flight, as well. I didn't
    know much about rotorcraft, but I knew a lot about "red lines," and
    Mitchell kept the airspeed at or above red line all the way. The
    little helicopter vibrated and shook a lot more than I thought it
    should have. I tried to reassure the cowboy-pilot I was feeling OK;
    there was no need to rush. But since he'd notified the hospital staff
    that we were inbound, he insisted we get there as soon as possible. I
    couldn't help but think how ironic it would be to have survived one
    disaster only to be done in by the helicopter that had come to my

    However, we made it to the hospital safely--and quickly. Soon, I was
    able to contact Lockheed's flight test office at Edwards. The test
    team there had been notified initially about the loss of radio and
    radar contact, then told the aircraft had been lost. They also knew
    what our flight conditions had been at the time, and assumed no one
    could have survived. I briefly explained what had happened,
    describing in fairly accurate detail the flight conditions prior to

    The next day, our flight profile was duplicated on the SR-71 flight
    simulator at Beale AFB, Calif. The outcome was identical. Steps were
    immediately taken to prevent a recurrence of our accident. Testing at
    a CG aft of normal limits was discontinued, and trim-drag issues were
    subsequently resolved via aerodynamic means. The inlet control system
    was continuously improved and, with subsequent development of the
    Digital Automatic Flight and Inlet Control System, inlet unstarts
    became rare.

    Investigation of our accident revealed that the nose section of the
    aircraft had broken off aft of the rear cockpit and crashed about 10
    mi. from the main wreckage. Parts were scattered over an area
    approximately 15 mi. long and 10 mi. wide. Extremely high air loads
    and g-forces, both positive and negative, had literally ripped Jim
    and me from the airplane. Unbelievably good luck is the only
    explanation for my escaping relatively unscathed from that
    disintegrating aircraft

    Two weeks after the accident, I was back in an SR-71, flying the
    first sortie on a brand-new bird at Lockheed's Palmdale, Calif.,
    assembly and test facility. It was my first flight since the
    accident, so a flight test engineer in the back seat was probably a
    little apprehensive about my state of mind and confidence. As we
    roared down the runway and lifted off, I heard an anxious voice over
    the intercom.

    "Bill! Bill! Are you there?"

    "Yeah, George. What's the matter?"

    "Thank God! I thought you might have left." The rear cockpit of the
    SR-71 has no forward visibility--only a small window on each
    side--and George couldn't see me. A big red light on the
    master-warning panel in the rear cockpit had illuminated just as we
    rotated, stating, "Pilot Ejected." Fortunately, the cause was a
    misadjusted microswitch, not my departure.

    Bill Weaver flight tested all models of the Mach-2 F-104 Starfighter
    and the entire family of Mach 3+ Blackbirds--the A-12, YF-12 and
    SR-71. He subsequently was assigned to Lockheed's L-1011 project as
    an engineering test pilot, became the company's chief pilot and
    retired as Division Manager of Commercial Flying Operations. He still
    flies Orbital Sciences Corp.'s L-1011, which has been modified to
    carry a Pegasus satellite-launch vehicle (AW&ST Aug. 25, 2003, p.
    56). An FAA Designated Engineering Representative Flight Test Pilot,
    he's also involved in various aircraft-modification projects,
    conducting certification flight tests.


    61-17952 being refueled a few days before the in flight break-up.

    Pilot Bill Weaver

    Local news paper

    I could not find any information or a photo of Jim Zwayer RSO as I would like to have posted it as well.
    But I did find out he was the only SR-71 crewmember to loose their life in the Blackbird.
    ;? ;w

  3. F14Scott

    F14Scott Luggage CLM

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    Sep 13, 2001
    Houston, TX
    NATOPS showed ejecting at speeds above 450 KIAS to be in the very dangerous/deadly category. I read one account of an F-15 driver who jumped out supersonic; he dislocated about everything, but survived. An SR-71 "ejection" at 3+IMN and FL780 with only minor injuries is amazing.
  4. M2 Carbine

    M2 Carbine

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    Dec 21, 2002
    Amazing. The forces must have been incredible.;P

    Good story.:)
  5. JCM298


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    Dec 25, 2002
    Tucson, AZ

    That was great story. Was it a magazine article or an excerpt from a book? If it's a book, can you give me the title and author?


  6. HKMark23

    HKMark23 Millennium Member

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    Dec 17, 1999
    Chez Bippy
    It was originally an article in a mag, something like Aviation Week or one of those, I forget. But it is reposted on a few web sites.

    Ive heard of some M+ ejections actually burning exposed skin on the crew. I know the "sled guy" (Col. Stapp) recived some burns at least once while doing the sled work at Holloman.
  7. Neal

    Neal Millennium Member

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    Jan 2, 1999
    IIRC, the holding pattern speed for the SR-71 is over 300 knots. It's an amazing airplane, and that was a great story. That is the kind of aviation story that keeps me on the edge of my seat. Thanks for posting it.
  8. ChopperEd


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    Apr 3, 2005
    500ft. AGL
    Yeah i was watching a History Channel program about Col. Stapp at Holloman doing testing. Apparenty he went around 600 or so mph ( correct me if I'm wrong) but he survived but did sustain damage such as temp. blindness and lots of bruises and dislocations. He eventually stopped the human testing so I was surprised to see this about the SR71 ejection. Good article.
  9. jungle


    Likes Received:
    Sep 15, 2004
    I would guess the maneuvers leading to the breakup slowed the aircraft quit a bit. The Q or air impact force at Mach 3 and 90.000ft is much lower than 450kts on the deck. I was on a missle shoot one time and the lead F-4 bagged the drone instead of the towed flare. The 580kt drone stopped in an amazing way as it became not aerodynamic.
    Any high speed ejection is dangerous and has the potential of tearing parts and breaking bones, for that matter so are low speed ejections.
    Good post HKMark23.
  10. Glockdude1

    Glockdude1 Federal Member CLM

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    May 24, 2000
    I have made alot of skydives from alot of different aircraft, but never from 78,000ft!!! I did jump from 17,000 in quincy 1998 from a Mullins king air.

  11. jacquejet


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    Oct 18, 2004
    Chapel Hill, NC
    As near as I can tell, Col. Stapp rode his rocket 29 times. His fastest was 0 to 632mph in 5 seconds. The deceleration took 1.5 seconds.
  12. Glockdude1

    Glockdude1 Federal Member CLM

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    May 24, 2000
    632mph to 0 in 1.5 seconds??? You know that hurt!!!

  13. veedub

    veedub CEO

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    Oct 9, 2004
    Here, there, everywhere.
    I know the F-15 guy. Well, it may be the same person. Jason Irwin. He used to be our CFO. Smart guy... but a total party animal. Didn't know when to quit. His mouth got him in trouble.

    Anyway, he was dog fighting over the Atlantic with another F-15. Low altitude. The lead plane banked left. Jason tried to cut him off. He ended up eating a flock of birds. Shredded his left engine. He bailed at 650 knots.

    The accident compressed his spine pretty good. He went in the AF at 6'0". When I met him afterwards he was 5'9".