747-8: Flight Report

A good yaw damper does wonders as well. Every Boeing jet from the B-47 onward has one. The old propeller airplanes behaved a little differently than the jets with their swept wings. I wonder if the Russian Bear (Tu-95) had similar issues?

 

The Bear's swept wing had anhedral that cancelled out the over-stabilization and the propensity for Dutch Roll.

 

And here is the -8 you didn't take delivery of the other day (friends were there to snap the pic, sharing here).
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There have been some really nice wing wags -

[ame]http://www.youtube.com/watch?v=3plCXaNc67w[/ame]

I can't find the video compilation that had 777 and 747 deliveries, some of the wing waggles were pretty impressive.

 

So did the B-47.

 

If you look closely, there is actually a wing wag there on that video... pretty anemic.

 

I'm not so sure that the B-47 had anhedral. I think that the wing was set up at jig position (flat and no load) and the nose up attitude on the ground gives it the appearance that it droops. Also it had a droop anyway with the outboard engine and span weight. I'm looking it up and checking with the guys at work. The B-52, sitting level to the runway, had 7.5 degrees of incidence in the inboard wing so that it could fly off the runway without rotating. The B-47 had that angle built into the entire airplane by virtue of the longer forward main gear, thus setting the wing at a constant high angle of attack. Bad deal on landing because the wing would continue lifting and they couldn't get adequate braking friction to stop the airplane.

 

I saw a video on Av Chat a while ago that I think was part of a commercial, the -8 was taking off coming into the camera and there were four distinct streams of white vapor coming up and over the wing that were produced by the nacelle vortex generators. It looked like smoke and a viewer asked what the "smoke" was from. I'm not certain what the phenomenon is caused by but the flow coming off the nacelle and strut leading edge got into a fight with the wing undersurface spanwise flow and got jammed up where the strut and wing leading edges meet and then set up a turbulent drag thing. It looks like they cured a lot of it by the unusual gap where the strut comes up under the wing and the rest was fixed by the nacelle vortex generator that diverted the air flow from getting into the argument with the other stuff. I'll talk to the guru's at work and get a more "techunul" explanation. That -8 is such a beautiful thing to watch. Never get tired of seeing the take offs.

 

The 747-8 can carry an amazing amount of payload.
Wikipedia says it has a max payload of 308,000 lbs.

Has the military ever thought of just using 747-8's to replace the fleet of aging B-52 bombers?
Wikipedia says a B-52 carries 70,000 lbs of bombs.

You'd think converting a 747-8 freighter to bomb-dropping duty would be very do-able.
.

 

It's probably a subjec for a different thread but i have heard that one before and from one aspect it seems to make a lot of sense. What I suspect kills it is the electronics side of things. Lots of electronic warfare gear that is already on board the BUFF. It would cost a lot up front to make the 747 up like that even though it might save money in he long term. They haven't even managed to re-engine the BUFF after years of talking about it.

 

I believe you are correct.

 

Gotta consider where the load is on the B-52 and where it is on a -8. The B-52 is a big railroad freight car with a wing mounted ON TOP OF THE LOAD and a pointy nose and long tail added. The load is under the wing at the MAC. The -8 load is spread from the 41 section clear back to the tail and located OVER THE WING with no place for a bombay that normally is near the MAC. You would have to cut a hole where the center section is. Okay everybody get the slide rules, pencils and knives, and rent a hotel room and carve a balsawood model of a B-52-8.has to be ready next Monday.

 

Apparently spotted in Anchorage later that day. Can't imagine a test flight from Paine Field to Anchorage and back.

Possibly another on the line for you next month?

 

There is another NCA -8 on the Flightline that was just recently painted. This may be your January delivery. Couldn't see a tail number though.

 

I just heard from the aero guys at work and the B-47 did not have anhedral. I seem to remember that it did have a yaw damper too.

 

Please keep us informed about your schedules while your here so that if we can't meet for dinner we can at least say hi n' goodbye.

 

That's a heckuva fast takeoff, Lou! Good thing Narita has long runways.....

 

Is the weight shown in that display something that was entered manually after being calculated or does the aircraft have the ability to weigh itself?

With that much weight, how much of an error would it take for it to be a problem?

 

I'm testing my recall here but I seem to remember that the MLG axles have strain gages in them to measure the load. I recall seeing the numbers ticking off and increasing during a refueling operation of a 747.