Knowledge

Can a Boeing 747 do a barrel roll?

Never knew a pilot training on the 747–400 to not roll the airplane while in the simulator. None of us were completely sure of the simulation’s fidelity but the control inputs and roll/pitch responses looked about right. Of course, there was no simulation of felt-Gs, either lighter or heavier in the seat, nor was there any vestibular feedback of the actual rolling motion; the visuals were awe inspiring, however, and persuasively realistic.

Technique? Pretty straight forward. Start at 280–300 kias, pitch to about 20° nose up and put in full aileron, control wheel to the locks. As the bank angle goes through about 60° let the nose fall and it will keep falling until about 20° nose low at the lowest point, perfectly inverted. Use slight forward pressure when upside down to keep the second half descent rate reasonable. Use about half rudder, no more: the sim didn’t like more than that.

As the wings came level, return to straight and level cruise flight (on heading, back on altitude, call “maneuver complete” like you do that for a living). Or! Pitch right back up to 20° and “unwind” your previous roll by going in the opposite direction. In the sim, kids. In the sim.

I’ve flown the real jet at Max Gross Takeoff Weight of 875,000 lbs (at the point we pushed the power up to start the takeoff), and while I loved the jet heavy I think that trying to roll it even given 340 kias would be “sporty” at best. Pretty sure you’d exceed every load limit Boeing had calculated before you got even 25% into your roll. Jesus! just, don’t.


Yes but I’ll qualify my answer by assuming you mean a regular aileron roll (see my point at the end). During type training, I’ve done it in the full size 747–400 airline simulator more than once and they’re a very accurate representation of the real aircraft (just for fun when we had a few minutes spare. It’s not part of actual training). Done properly, a roll is a low stress manoeuvre.

Having said that, the 747 has been involved in at least one accident where the aircraft exceeded the stresses you’d find in an ordinary roll and performed some extraordinary manoeuvres as the crew struggled to regain control (China Airlines Flight 006). They and the aircraft survived and flew on to landing.

Also note that a Boeing 707 did a roll during a sales demonstration flight (Pilot Tex Johnson in 1955). It was both at (relatively) low altitude and in front of a crowd. Search for it, there are many photos and a film. Back to the “barrel roll”. Most media and general public incorrectly use the term “barrell roll” when they really mean an aileron roll.

An aileron roll is when the aircraft simply rotates 360 degrees along it’s longitudinal axis. Although an initial use of elevator usually precedes the manoeuvre, the primary input during the roll is aileron. A barrell roll is when the aircraft appears to scribe a path as if flying around the inside of a giant barrell.

This manoeuvre has two primary inputs used throughout the manoeuvre, aileron and elevator. I’d bet the ‘plane could pull this off but have never tried it.

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