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[i]Jay's account of the STS-3 approach and landing is only partially correct. He should have asked me to review his report before posting it. The most objectionable part insinuates Chris Kraft is unreasonable and that he ended my flight career because he was unhappy with the landing. That kind of speculation is out of bounds and publishing such rumors is poor journalism. Chris is objective, candid, an original space pioneer, and a dynamic, effective leader. Reports and rumors about how the STS-3 approach was flown and what "must have occurred" (but didn't) have come and gone over the years. Interestingly, none of these reports and rumors was preceded by asking me what happened, except for the recent conversation with Jay. Incidentally, Jay and I did not discuss anything about Chris Kraft's reaction to STS-3, as alleged in his commentary. The fact is that Chris Kraft and I have always enjoyed cordial relations both professionally and socially. In a private, post-mission conversation, he did not criticize any part of STS-3, including the landing which was within shuttle limits. He was pleased with the overall outcome of the mission and brushed off the landing as acceptable under the circumstances. I consider Chris as a personal mentor and friend in my career at NASA, and he never put me under the gun. It was made clear to me that I could command another flight, but after proceeding with early training on a flight that was about two years downstream, I decided it was time to be moving on with the inevitable next phases of life's journey before it was too late to get started. Had I been able to fly again sooner I probably would have stayed around to do so, but I made the right choice at the time and have never looked back. Life is good! The STS-3 approach problem is simply explained by stating that the auto system, while it correctly controlled the nose of the ship on the outer glide-slope, through the preflare, and on the inner glide slope, it did a poor job of modulating the speed brakes to control the airspeed on the outer glide-slope. The auto system also fully closed the speed brakes 1,500 feet before I would have done so manually. This resulted in a substantially higher speed coming out of preflare and being closer to the ground (further down the inner glide-slope) when the gear were lowered procedurally based on airspeed (270 knots) rather than altitude (gear down was changed to 400 feet after that). I took back manual control when stabilized on the inner glide-slope by depressing the "Manual" button on the eye-brow panel; not by moving the hand-controller out of detent, as has been rumored. It was mandatory to land in manual control because the landing software was not yet fully developed and tested. The auto system also lined-up the shuttle slightly to the right of centerline, which I decided not to correct that close to landing. In essence, the auto system did not fly the approach I would have flown manually, but it was not unsafe. So my job became one of salvaging a less than perfect approach, which I did, but not as well as I would have preferred. Further, we did get the data required by the autoland test objective, and we also proved the well-worn adage of our first flight instructors; 'To make a good landing you must fly a good approach'. Incidentally, we never experienced this speedbrake control problem in simulation. The simulators always modulated the speedbrakes in small increments to control speed perfectly. If the flight software had been installed in the simulators we would have been ready for this problem, except that we would have rejected the autoland test objective altogether until the flight software was capable of smooth speed control. We vigorously insisted on simulating with flight software installed, but this requirement 'fell through the crack' somehow in the fixed and motion-base simulators as well as the Shuttle Training Aircraft. Unfortunately, we didn't know of this oversight until we flew STS-3. With respect to the "wheelie" right after touchdown, the nose began to drop before aerodynamic braking was complete at 160 knots, so I tried to hold it off with a short nose-up pulse on the hand-controller. The nose did not react quickly enough for me, so I gave it another short nose-up pulse. This caused the nose to rise rapidly whereupon I lowered the nose to the runway manually. I was told later there was an instability in the longitudinal control software in that landing configuration causing the unexpected pitch-up. Perhaps there was. In any case, we learned a lot with no harm done; that's why we do test flights. And that's why I have moved beyond the rumors and speculation on this whole subject, and that's why it was of little consequence to Chris Kraft. The autoland system was scuttled after that experience because it was not "certifiable" in the aviation sense of "certification". Moreover, our experience implied that if the autoland failed close to the ground, it would force a "late takeover" in a possibly unrecoverable attitude. Thus, it would be better to not fly the autoland system down to a position that would be potentially unrecoverable. I think some sort of autoland system has been installed in case they would want to try to recover a damaged shuttle, incapable of safe reentry (like Columbia) that was abandoned at the ISS, the crew having been ferried home from the ISS in a rescue shuttle. [/i]
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