Could it do a barrel roll? An Immelman turn? What?
If the president were in an F-14…then certainly. 
(AF1 being whatever plane the Pres is on)
The current regular AF1’s are a pair of VC-25A’s, which are basically modified 747’s. Here’s a prior article from Cecil
Basically it sounds like it’s theoretically possible, but would be very foolish to attempt.
There is this video which seems to show a 747 doing one, but I can’t vouch for it’s authenticity.
(Assuming you’re being facetious.)
It was a joke…I just found the video funny.
Cecil: Is it possible to loop or roll a 747?
As I linked to above.
I agree.
the plane could probably take it.
The pilot would be the weak link and he or she would probably lose control of the aircraft and crash.
I don’t totally understand Cecil’s reasoning for why a 747 would be any less capable of doing a barrel roll than Tex Johnson’s 707 was. As I understand it, the basic issue is whether the plane can maintain enough speed throughout the maneuver to avoid stalling or losing a lot of altitude while the wings are near vertical. That would depend on the maximum airspeed, stall speed, TWR and the roll rate. Of those, I’m fairly sure the first three at least are all better on the 747 than on the old 707 prototype and I’d be surprised if the roll rate was really all that different given the bigger and better control surfaces especially on newer generation 747s.
Maybe it was a little less clear with the 747 variants flying around in 1978 when Cecil wrote the column, but at least in my non-expert reckoning I’d imagine the current crop of 747s would be at least as aerobatically capable as the old 707.
(Of course, as Tex demonstrated, the 707-based Air Force Ones used from Kennedy to the first Bush could definitely do a barrel roll.)
Any plane at all can do a barrel roll, provided that it starts with enough altitude. A barrel roll puts exactly the same strains on an aircraft as normal level flight does. Do it smoothly enough, and the first class passengers won’t even spill their drinks.
In normal level flight the wings are both positively loaded with nearly equal loading, in a roll they have opposite loading that can be very unequal. Almost everything a plane does puts different strains on the whole structure than they would have in normal level flight.
If your plane has poor roll rate, and you want to maintain positive wing loading, then your barrel roll path will have a very large diameter. That means either:
A) your peak height (at mid-maneuver) will be much higher than your starting altitude, or
B)your final altitude will be much lower.
If you have good thrust-to-weight ratio, then you can maintain your airspeed while you pursue option A (steady positive g’s). If not (and I suspect this is the case for a 747), then you end up with option B (weak positive g’s at the start of the maneuver, finishing with high positive g’s). If you go with option B, it remains to be seen whether your final airspeed will be in excess of the max recommended speed for that aircraft. Johnston did it with the 707, but that does not mean that “any plane at all” is capable of a barrel roll without exceeding its recommended performance envelope.
There’s no reason you couldn’t maintain positive 1 g throughout the roll. Such a roll would cost you a great deal of altitude, of course, which is why I said you had to start off high enough.
It would cost you a great deal of altitude, yes, and in the process you’d build up a lot of airspeed - possibly more than the aircraft is built to handle. With the lift vector rotating through a complete circle, the time-averaged lift for the duration of the event is zero, so in terms of final trajectory/altitude, it’s as if the aircraft were in freefall the entire time. SWAG = a 747 can complete a roll in 16 seconds, assuming 450 MPH air speed, starting the maneuver from level flight, 16 seconds of freefall adds a vertical component of 350 MPH. Pythagoras says your final velocity is 570 MPH, at a final descent angle of 38 degrees. That’s a pretty dicy final state. I’d be curious to see someone try this in a flight simulator (someone here must have X-Plane or MSFS) and report on the results. Do they exceed max airspeed before they can pull out of that dive?
You can start the maneuver with less airspeed and/or greater altitude, but I expect that will reduce your available roll rate, which means greater final vertical speed (and altitude lost).
Short version: I don’t believe it should be taken for granted that any aircraft can perform a barrel roll without crashing.
Hm, true, I wasn’t considering the airspeed.
Lot’s of erroneous info on this thread.
As someone else said, yes, any aircraft can be rolled. If done correctly (barrel roll) you could maintain 1 G and as someone said, not even spill your drink.
(aileron roll will be a bit different)
Attached is a Wiki article on Dynasty 006, a 747-SP that rolled inverted, briefly became supersonic, and recovered over the Pacific Ocean…with a full load of passengers.
As a pilot with more than a couple of hours as pilot in command and having been an airplane nut , working almost my entire life in aviation, talked with thousands of pilots etc., etc.
Except for some strange machines that it is a stretch to call an airplane, and lets limit it to fixed wings and actual 3 axis control, of which airliners are, for the most part, can do a properly executed barrel roll.
This includes gliders. Even a few helicopters & ultra lights.
The aircraft does not ever go neutral G or negative G doing a properly executed barrel roll.
I have personally seen a few larger planes do them. I know pilots who have done them that will not admit to doing some things.
Anyone ever hear of Bob Hover?
I have never personally rolled any aircraft larger than a C-310 or older 540 Aero Commander while being the pilot. I have been on some great rides that were flown buy other pilots.
Not all aircraft enter into the barrel roll exactly the same, Pitts Special, C-310, B 747 for example.
This goes for most aircraft clear back into even pre WWI aircraft.
So all the arguments in the world do not mean anything to the airplanes or pilots. The Piper Cub & the B 747 are both capable of doing a barrel roll.
Oh, and on preview, the airspeed will not be anywhere near excessive if the barrel roll is done properly.
That must have been exciting … :eek:
I’m not sure what the relevance of that incident is. In the course of its not-a-barrel-roll supersonic 5-g maneuver, it sustained major airframe damage. The wings were plasticly deformed, and the tail…well… :eek:
OK, so lay it out: how would you achieve a barrel roll in a 747 while remaining within the safe flight envelope (g-load, airspeed, etc.)?
It always helped Bob Hoover (who flew chase plane for Charles Yeager’s first supersonic flight!) to pour a glass of lemonade from a pitcher throughout the roll. This gave him a nice reference of postive G maintenance. And yes, I’m kidding. At least about the purpose.
Like I mentioned above, though, what flight characteristic would make an early 707 capable of barrel roll (which I presume was the “option A” variety) but not a newer generation 747? I’m almost certain the TWR is a lot higher on the 747.