747-8: Flight Report

That white line looks like a pretty impressive rate of climb, if that's to scale looks more like you are flying an F15

Great pic's as always Lou

 

Thanks for posting this stuff on the 747, Lou. It brings back a lot of things on which I worked. The leading edge slats that change curvature were referred to as Variable Camber Kruger flaps. They are made of fiberglas and route the flow up and over the wing leading edge and intercepts it before it gets to the stagnation point at the lower surface of the wing. More efficient than the flat Kruger flap, they are placed farther out on the wing span and farther aft of the of the flat Krugers that stall before the VCK's, producing a more normal stall. Clever design.

 

Isn't there a sped limit under 10 k? Looks like 268 indicated. Am I wrong?

Art

 

Thanks for the continued posts & pics.. fascinating and much appreciated to see whatever you can continue to share.

 

If you look at the pic at the top of this link, you can see all of the above:

The 747:

Krueger flaps in action (Fiberglass honeycomb).


All 3 AC PACK intakes (open) and outflows (closed).

In glorious color.

https://en.wikipedia.org/wiki/Krueger_flaps

 

Again, thanks for posting these lovely pictures. I had the privilege of working on the ECS system on the 767 and 777. The outflow doors are open in flight but as you mentioned, they are more in-trail than they are on the ground. A huge amount of air flows through that system after being in-taked by the scoops. The air is filtered and refreshed every 30 seconds.The NACA scoops shown, by the way, were not the most efficient on a curved surface like the under wing fairing and they were changed to simple ramps on the 777 and subsequent aircraft. That cabin pressure outflow valve on your airplane is a far cry from those on the 707's when smoking was allowed on the aircraft. The outflow valves on the early airplanes were were gummed-up with a sticky brown goop that trailed aft of the exhaust on the fuselage skin. Coal tar from cigarette smoke. It not only gummed up some of the electronics but discolored the interior decorative panels. No one realizes now how much cleaner the interior environment is since there is a no smoking rule in effect on airliners. I have posted it before but I will mention the episode where a customer ordered a replacement for a damaged interior panel and rejected the replacement because it didn't match those in the airplane. After an extensive investigation it was discovered that the airplane interior had been discolored by cigarette smoke and we could not match the color. Time for a thorough cleaning.

 

One of my diagrams of the flat Kruger flap.
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I forgot that those L.E. flaps were driven by an air turbine that makes a helluva racket when they run. A single shaft running from wing tip to wing tip operates them so that there is less chance of having asymmetrical flap extension. I will try to dig up the diagram of the VCK operation.

 

thanks, shows me what I didn't know.

Art

 

Lou,

do they ever deny a request to deviate around weather? How much "RED" can you fly through? I've heard that UPS/FedEX guys fly right through most stuff and was wondering if that's a myth or not?

Thanks!

Chad

 

Not Lou but I have flown a bit..... There is some flexibility in deciding what to fly through and what an experienced cargo hauling crew may choose to fly through is perhaps a bit different from what a passenger aircraft may accept. To say that some will fly through "anything" is just nuts because, if nothing else, somebody will probably ask how all the dents got in the aircraft from the hail.

I'm not all that familiar with what kind of weather radar commercial aircraft use but the variety of radar can even play a big part of it. I grew up using a high power radar that was actually a bit dangerous if you pointed it at stuff on the ground. It was old technology but a skilled operator could use it to assess the weather and truly determine what should be avoided. The new low power color radar offers is a lot "smarter" in some ways but it still seems to show a lot of red when its really not all that bad just yet. For a period I flew with a mixed squadron and it was interesting to see how there is a tendency to just trust the radar and avoid all red rather than tune and identify what the real weather threats might be. Aircraft with older and more manual radars would fly right through areas with zero difficulty where the guys with newer radars would just blindly trust the box. This can sometimes mean the difference between getting in someplace or diverting to another field. Some of my more vivid memories of flying have been picking a course through thunderstorms in order to make it to a destination.

Again not Lou.... I have never heard someone denied a request to fly around weather, even if they were just being overly cautious.

 

I'm not Lou either, but yes, occasionally they will deny it. Not common, though. Usually, it involves other traffic, and they will ask you to go the other way instead, or will try to negotiate something which works for everyone.

I remember years ago hearing it when heading south to Las Vegas-- the airspace there is a corridor between two restricted areas. The guy wanted to deviate, and ATC said they couldn't authorize it because of the restricted area. The airline guy said he was doing it anyway, and ATC told him to "proceed at your own risk." He probably declared an emergency, but I don't remember for sure. He was certainly using his emergency authority.

ATC does try to be as helpful as they can be, and generally they will be very accommodating.

As for FedEx and UPS, I wouldn't be surprised if, on average, they were more willing to fly through turbulence and weather than a typical pax carrier. However, it greatly depends on the individual Captain.

I know I'm more willing to fly through stuff on an empty leg than I am with passengers, and I don't see why the same wouldn't apply here. However, in no case would this have anything to do with safety, just comfort.

 

[ame=http://www.youtube.com/watch?v=J-qPtWc4heA]Fed-Ex Diversions to Memphis 8/23/03 - YouTube[/ame]

The classic radar feed video of Memphis during FedEx rush hour. Note they all fly around the red during their approach and fly in circles when the 'red' is over the airport. A couple even divert, likely due to fuel.

 

In other 747-8 news (passenger not freighter):

Airbus loses dispute over 747-8 advertisement

 

if memory is close to correct... the 20 mile rule came into play when a plane went down on approach into Atlanta when it got hit by both extreme hail and lightning...

prior to that the norm for separation was 5 miles... research studies show that lightning can reach out 20 miles or more from the center of activity... one does not need to be under a cloud for lightning to strike... from personal experience I had lightning strike a nearby tree, we were in full sun shine with some cumulous clouds without any hint of rain or any storm activity in the immediate area

I've taken a few lightning strikes while flying without any immediate damage... only after inspection the aluminum skin was damaged where the lightning hit... the hit area shows erosion or perforation in the aluminum...the eroded area looks rough like sponge...

 

The Pan Am 707 that crashed in Maryland in 1963 was in a holding pattern outside the thunderstorm that was keeping it from landing in Philadelphia when it was hit by the lightning that led to the aircraft's destruction.

And the 767 that I was on that (I believe) was struck by lightning was also holding in the clear outside the cloud near Atlanta when it was apparently hit. (I saw a bright flash in the corner of my eye that was very near the wingtip and could actually hear the thunder inside the airplane!)