Book: Handling the Big Jets by David P. Davies


Fascinating look into the history of aviation

David P. Davies
Handling the Big Jets: An explanation of the significant differences in flying qualities between jet transport aeroplanes and piston-engined transport aeroplanes together with some other aspects of jet transport handling
(British) Civil Aviation Authority, third edition, 1977 (originally published in 1967)
ISBN: 0 903083 01 9
The third edition (1972) has been reprinted and copies are available for UKP 35.00 plus shipping and payment charges from HTBJ@hyman.plus.com
319 pages

David P. Davies was the chief certification test pilot for the British Civil Aviation Authority (the British equivalent of America's Federal Aviation Administration) beginning 1949 and he worked for them until his retirement 33 years later. He wrote Handling the Big Jets for pilots of piston-engined airliners who were transitioning to flying jet airliners. It was originally published in 1967 and was revised most recently in 1971. Though it's naturally a bit dated by now, the book is apparently still considered valuable by pilots.

Little needs to be said about the book. People who will want to read it very likely know they do by now and it will be of little interest to most people. To a geek like me, the book provides a fascinating look, though a somewhat indirect one, into a particular era in the history of aviation. Things like noise-abatement departures were new and the flight simulators of the time didn't have all that much fidelity to the airplanes they were trying to simulate (though Mr Davies looks forward to a time when they will). The requirements of high-speed aerodynamics mean that it's very difficult or impossible to engineer good flight handling qualities into an airplane by purely aerodynamic means. Other means, such as stick-shakers and stick-pushers were new and pilots didn't necessarily trust them yet. Air-data computers existed, but they used cams, not electronics.

Reading the book you also get a feeling for the sort of person Mr Davies was. And it's easy to imagine that there must have been a few tense moments in the cockpit as he acquired all the experience he had. He casually mentions having flown a 747 to mach 0.98 (it is normally limited to mach 0.89). He describes flying a go-around from 1000 feet in a 747 with two engines on the same wing reduced to idle thrust. He did that on a gusty day in bad weather. Running a jet engine considerably beyond its rated thrust, he tells us, "is not immediately destructive occasionally" (p. 79). And, "The inverted dive will be obvious by all the loose equipment flying around the flight deck and the fact that you are hanging on your straps" (p. 246). And then there's, "a dark and dirty night when you have a load of passengers is no time to find whether you or the aeroplane is master of the situation" (p. 105).

It's a bit haunting to read Mr Davies's description of the results of unrecoverable stalls:

    There is no point in discussing the irrecoverable
    case any further, except perhaps to say that those
    aeroplanes which have been lost in such
    manoeuvers finally reached the ground
    substantially level laterally, having defied all
    efforts to roll or spin them out of the stabilized
    condition; only slightly nose down in pitch, with
    little or no forward speed; at an extremely high
    incidence; rotating only very slowly in yaw; with (in
    one case) all the engines flamed out because of
    being exposed to such massive angles of
    incidence; and finally with an enormous vertical
    velocity. (pp. 122-123)

and compare it to the French Bureau d'Enquêtes et d'Analysys interim report (caution, large PDF) on the crash of Air France flight 447:

    Observations of the tail fin and on the parts from the
    passenger (galley, toilet door, crew rest module)
    showed that the airplane had likely struck the surface
    of the water in level flight, with a high rate vertical
    acceleration. (p. 40)

There are more than a few things to be learned from the book despite its age.

Posted: Wed - August 5, 2009 at 06:47 PM   Main   Category: 

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