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WOW! The rate of climb was very impressive on the initial take-off. Don't know much about commercial aircraft but I was impressed.
 

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Great video. Thanks for sharing!

What folks sometimes don't realize is that loading these big girls up with fuel, passengers, and other payload more than doubles their weight. On those rare occasions when you get to fly one empty, the performance can be breathtaking.

A note about the initial climb: this is a maneuver known as "trading kinetic for potential". What that means is that you build up quite a bit of speed (kinetic energy), then pull the nose up to a steep angle and trade that speed for altitude (potential energy). As you saw in the video, he couldn't sustain that climb for long, and had to do a fairly aggressive pushover before the speed got too low (in which case you perform another crowd-pleaser: the stall/spin into the weeds).
 

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As you saw in the video, he couldn't sustain that climb for long, and had to do a fairly aggressive pushover before the speed got too low (in which case you perform another crowd-pleaser: the stall/spin into the weeds).
Now that I am familiar with...in my younger days I could sustain my rate of climb but was a "pushover" for cocktails which would lead to the aforementioned performance of a stall/spin into the weeds....
 

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Great video. Thanks for sharing!

What folks sometimes don't realize is that loading these big girls up with fuel, passengers, and other payload more than doubles their weight. On those rare occasions when you get to fly one empty, the performance can be breathtaking.
A note about the initial climb: this is a maneuver known as "trading kinetic for potential". What that means is that you build up quite a bit of speed (kinetic energy), then pull the nose up to a steep angle and trade that speed for altitude (potential energy). As you saw in the video, he couldn't sustain that climb for long, and had to do a fairly aggressive pushover before the speed got too low (in which case you perform another crowd-pleaser: the stall/spin into the weeds).
So .... empty, a 787 can do an Immelmann loop? :eek:mg:

Years ago when the movie BLUE THUNDER came out there was a quip between Roy Scheider's character and a competing pilot that "helicopters can't do loops" .... except late in the movie when this pilot if flying a Loach against BT Scheider actually DOES A LOOP in the BT to get behind the attacker (if you look REAL CLOSE on DVD you can tell the chopper is a RC model in the loop shot, though). Later on I obtained a video showing AH64 Apache choppers doing all sorts of aerobatics you might think a chopper couldn't do -- except they seem to be able to ....:rolleyes:

I like AIRWOLF better. :cool:
 

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As I recall the MBB B.105 was the first rotor to loop and roll.
The original 707 did a simple one G roll to attract attention.
Geoff
Who notes it's covered in the documentation...piles and piles of documentation...
 

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Discussion Starter #10
Geez, you can't do that with a helicopter. Can you? My rides in hueys were not that exciting if you ignore being shot at.
 

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Geez, you can't do that with a helicopter. Can you? My rides in hueys were not that exciting if you ignore being shot at.
I dunno, Bearcat. Likely the pilot of the Huey you were in was not trying to do fancy aerobatics, just survive. As I said ...I've seen films of Apaches do some wild things.
 

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Boeing bet the future of the company on the 707 and there were rumors that it was unstable. Boeing knew this was rubbish. Test Pilot Tex Johnson had done a one G alerion roll a couple of times during test flights. The one everyone remembers and that was captured on film occured during a demonstration flight over Lake Washington outside of Seattle, on August 7, 1955 in the 367-80 prototype. Rumors of instability were put to rest.
I've heard it called a barrel roll, an alerion roll and Tex called it something else in the video. I'll let our resident pilots explain the difference. One wonders how much of the flight control system has to be shut down on a modern airliner to allow such a manuver.

 

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You had it right; what he did was an aileron roll. In an aileron roll, the aircraft simply rolls around it's longitudinal axis (the axis that runs lengthwise through the fuselage.) Since the wings are vertical with respect to the horizon twice during the maneuver, it's not possible to hold the nose up, so your pitch attitude drops. You compensate for this ahead of time by entering the maneuver nose-high (as you saw Tex do).

What Tex calls it in the film is a "one-g maneuver". What he's saying is that it doesn't stress the aircraft any more than level flight does, it keeps you firmly planted in the seat, and it keeps the fuel safely at the bottom of the tanks, where the pumps are.

A barrel roll is a different maneuver entirely; it's a huge spiral through the sky. It's primary use is in aerial combat, to dissipate excess energy relative to another aircraft. Assume you see an enemy aircraft, and you're behind him, but you've got a huge overtake which threatens to take you out in front of him, where you will quickly transition to "target". In order to dissipate the excess energy, you pull the nose off to one side, say about thirty degrees, then pull into a huge arcing roll, continually keeping him thirty degrees off your boresight. You never lose sight of him, and, by traveling a much greater distance through the air, you're able to remain behind him.

To illustrate in a different way, imaging watching airplanes performing the two maneuvers while leaving smoke trails. The one doing an aileron roll would leave a gracefully arcing trail, like a rainbow. The one doing a barrel roll would leave a huge corkscrew.
 

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I dunno, Bearcat. Likely the pilot of the Huey you were in was not trying to do fancy aerobatics, just survive. As I said ...I've seen films of Apaches do some wild things.
The CH-53 Sea Stallion/Super Stallion can do some pretty neat tricks too, including loops and barrel rolls--stuff you'd never expect from one of the biggest choppers in the free world.
 

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I was going to make a snarky comment about the 787's "spontaneous combustion" option... but that would be wrong.
What happens when you let the s***-for-brains McDickless Idiots shove the Airliner EXPERTS at Heritage Boeing out the door...
 

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Earlier in this thread we were discussing the difference between aileron rolls and barrel rolls. This video gives a perfect illustration of barrel rolls.

I used to teach formation flying, and I'm impressed with this performance. The jets trailing red smoke are doing nearly perfect barrel rolls around the smoke trails of the formation. Keep in mind also that, since they're traveling a greater distance through the air than the formation, they are maintaining a higher airspeed.

http://i.imgur.com/pe0fWrW.gifv
 

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Discussion Starter #18
Wow! That's a great picture Cap'n.
 

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Who were those masked men? (Sorry...on a series western kick right now)

But Jeez Louise that was amazing!

And really...anybody know who they were?
 

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At first I thought it was the Italian team, Frecce Tricolori, because they're flying Aermacchi's, but the smoke colors are wrong (no blue in the Italian flag). A little Googling indicates that it's the team from the United Arab Emirates, called Al Fursan, who also fly Aermacchi's.
 
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