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Reading The Crash Detectives: Investigating the World's Most Mysterious Air Disasters by Christine Negron, I came across the following description, in relation to some early de Havilland Comet accidents, notably G-ALYZ at Rome (Oct 26, 1952):

Pilots were instructed to nurse the plane off the ground by raising, lowering, and then slightly raising the nose again at takeoff speed, a technique called the "Foote takeoff"

I was quite puzzled by this.

  1. Has such a technique really existed? "Foote takeoff" returned literally two search results, one pointing to the book mentioned above, the other to another book on the Comets.
  2. What exactly is the point/purpose of "raising, lowering, and then slightly raising" the nose? Why not simply rotating at VR?
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The 1952 takeoff accident you read about was piloted by Captain Harry Foote. The technique got its name after the accident, which Captain Foote was blamed for (Comet! The World's First Jet Airliner, page 125).

Pushing the nose down is not standard though, rather a corrective measure to over-rotation past 6°. The article quoted below covers the proper technique and the 1952 accident:

The B.O.A.C. Training Manual recommends the following take-off technique:

At 80 kts. the nose should be lifted until the rumble of the nose wheel ceases. Care should be taken not to overdo this and adopt an exaggerated tail-down attitude with a consequent poor acceleration.

(...)

Take-off tests by the manufacturers have shown that a constant 6° incidence of fuselage during the ground run gives good results for distance run and for climb-away behaviour. They have also shown that an increase of incidence to 9° results in a partially stalled wing inducing high drag which appreciably affects the aircraft’s acceleration, and that the symptoms are noticeable to the pilot as a low frequency buffet. The aircraft recovers from its semistalled position if the nose is pushed well down. [emphasis added]

(...)

It was the opinion of the investigators that the accident was due to an error of judgment by the captain in not appreciating the excessive nose-up attitude of the aircraft during the take-off.

(flightsafetyaustralia.com)

As @RAC said, VR didn't exist. Judging by the historic FAA regulations, VR and the takeoff speeds in general for Part 25 came about in the mid-60s.

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At the time of the Comet disasters, Vr did not exist. The standard takeoff technique was what was used on all previous airplanes - line up, release the brakes, apply full power (derated thrust did not yet exist), accelerate, apply some back pressure to take the weight off the nose wheel, start feeling the airplane off the ground.

The problem was that the low thrust of the early jet engines was easily beaten by the drag of a wing over-rotated early in the takeoff run, and the airplane would run off the far end of the runway in a non-accelerating nose-high attitude. So the Foote technique was a way of taking the weight off the nose wheel in a consistent and calibrated way, and to not over-rotate.

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"Naked Pilot" by David Beaty suggests that this technique was introduced by engineers following Foote's accident.

Behind the scenes, BOAC and de Havilland were worried too. The manufacturers had been doing further tests and a new take-off technique was introduced. The nose-wheel had to be lifted off the ground at 80 knots, but afterwards it had to be placed on the ground again - a most extraordinary manoeuvre.

Beaty's piece suggests the technique was an incomplete attempt to salvage the Comet without really understanding the issues involved in the crash.

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