Automatic touchdowns
At the risk of sounding bravado, but for Barry Schiff's files, I want to give him an historical note to go with his "Turbine Pilot: Low-Down Tricks" (December 1993 Pilot). I am sure that he may hear from others that he and Jimmy Doolittle did not corner the blind landings market.
On a late-spring morning in 1949 at the CAA's Landing Aids Experimental Station in Arcata, California, I made a series of four landings with a measured 200 to 280 feet forward visibility and a measured 0- to 15-foot variable ceiling. These were made on one of many days of instrument landings trials. They were the first jet instrument landings and were made in an F9F3 Panther jet fighter to evaluate various approach lights and, incidently, to see if it was feasible to land jet airplanes in all weather. We did not have an autoland system. We didn't even have an autopilot. All approaches and landings were "guts ball" manual types, with the help of a magnificent GCA crew and a lot of mutual trust.
In the category of incentives to do it right the first time, the runway was 5,000 feet long with a 20-foot overrun that ended at a cliff, which in turn dropped 100 feet to the Pacific Ocean.
Retired VADM Donald D. Engen AOPA 471740
U.S. Navy
Alexandria, Virginia
The L-1011 aircraft was in fact certified in England by the CAA to Category IIIc. It was not certified operationally to CAT IIIc because of limitations of ground equipment, specifically the inability of emergency vehicles to locate the aircraft if necessary.
The Trident was certified for CAT II automatic landing in September 1968. I believe a version of the Boeing 727 was in fact certified before the Trident. Incidentally, I do not recall any influence of the space shuttle on the L-1011 system design.
I retired from Collins in May 1991 as engineering manager in charge of flight control design so have no official input to you, but my perspective (as an engineer) on automatic landing performance is that the L-1011-500 with the digital system performs better than the original analog system, which I believe Schiff flies, and that the Boeing 747-400, which was the last aircraft I saw certified with a Collins autopilot, works better still. My old team is now busy on the B-777. I'm sure that will be just as good as the others, and I hope Schiff gets to fly it.
John C. Hall AOPA 591540
Cedar Rapids, Iowa
Being an ex-British Airways pilot who emigrated to this wonderful country, I nevertheless retain some joy in the achievements of my own countrymen. Specifically that we were quite proud, even if at the same time a little wary, of the fact that the de Havilland Trident carried out the first automatic touchdown on a scheduled passenger service when it arrived at London Heathrow from Nice, on Tuesday, May 16, 1967.
Certification had been achieved by what was then British European Airways on April 19, 1967. Indeed, by the time I left the airline for America in 1975, Tridents were operating to CAT IIIb minimums — i.e., a 12- (yes, 12) foot decision height with 90 meters runway visual range. I distinctly recall the overshoot procedure, which mentioned that the wheels may brush the ground though you may never have seen it.
Bruce P. Butlin AOPA 965117
Parachute, Colorado
Crew coordination
Regarding "Turbine Pilot: Lowering the Minimums" (December 1993 Pilot), the author would have served the aviation community better had he told the perplexed controller at Memphis he was CAT II-certified when obviously queried (even if not directly) on the subject. An approach in a Piper Navajo during CAT II conditions is likely to generate an inquiry, albeit an indirect one. However, the message to the pilot ought to be crystal clear, as it apparently was (in this case), according to the author himself. Instead, he elected to let them (the controllers) guess, and he continued to bait the issue. That's not what good communicative interaction is all about. Pilots sometimes fail to realize that crew coordination and positive communications extend beyond just the cockpit.
Robert J. Rendzio AOPA 930350
President, Safety Research Corporation of America
Ozark, Alabama
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