gums

Been lurking for a bit and finally had to comment about the AoA issue.

Flew only three jets with an AoA indicator - first had a big round steam gauge and we never looked at it unless we were maneuvering close to the "pitch up" boundary ( VooDoo), although we should have used it a lot more for approaches versus the 175 knots and 5 knots for each thousand pounds of gas above 3,000 pounds.

Second two had HUD's, and both had the AoA bracket once gear was down for approaches. The SLUF had it full time, but we only saw it when pulling a lot on dive recovery or a turning defensive maneuver. Viper only showed the "bracket" once gear was down, as we had the "protections" like the 'bus for AoA with gear up, heh heh.

As Smilin' and Retired and 'bird and OK have said, the AoA indication is really neat for approaches, as you can verify the T.O. approach speeds without lottsa calculations about weight and such. Simple crosscheck between the HUD speed and the AoA to ensure your configuration was correct, and I learned the hard way. Bumped flap lever before trailing flaps down, but leading edge flaps already down. So had correct stall protection AoA, but actual speed was higher than it should have been and I almost overshot the RWY.

Where the AoA indicator helps is close to a stall and on approaches, where you are - close to a stall!! Normal cruise or even moderate maneuvering doesn't require an AoA indication.

Looking at the 'bus displays, I don't know how you could put an AoA indication on the screens that would be easy to interpret/use. If there was a HUD, then no problem - use the "bracket" as we see in the Viper, Hornet, Eagle, Lightning, Jaguar, Space Shuttle, et al.

I have a hard time with commercial jets that don't have a HUD. Flying an approach in poor weather is so much safer and easier that I would demand it. A manual ILS is really neat with a HUD, and the Space Shuttle videos of their landings show how it works for their landing, so find some. Cross check with the steam gauges/ glass cockpit displays is real easy. You also have some neat things like actual inertial flight path vector, speed/altitude/vertical velocity right there on the sides of the display. So the AF447 crew could have seen the alt unwinding real easy, and the speed bouncing about from whatever to 107 knots.

Our dinosaur FBW ( father of the 'bus system) used the fixed stick and pressure sensors versus actual movement. This was because we routinely maneuvered at high body rates and gees. So having a moveable stick could have inadvertant inputs due to the forces on your arm. Despite concerns by the wimpy USAF HQ, it took us maybe 2 or 3 seconds to adapt to that stick once you rotated for your first takeoff.

Unless the AF crew was in severe turbulence involving high roll and pitch rates, there's no excuse for inadvertant stick inputs. The crew held back stick and could not fathom a stall that was so benign. No nose slice, no high roll to one side or the other, no extreme buffeting, etc. Of course, stall warnings and maybe overspeed warnings. Couldn't find the overspeed warnings in the BEA reports, but maybe that was a concern to the crew.

mm43

Chris Scott; TTex600;

Sorry about the confusion over the Google search string. I didn't check after posting, or I would have noted the url had shown as a link.

Anyway, the format is as posted by TTex600, e.g. 'search term' site : url, but the url needs to be the basic domain name without the http//: or www. Try the following by copying and pasting into the Google search box:-
- which returns all posts in pprune/tech-log by page number containing those search terms. (Note - had to place the terms in 'code' as the pprune site uses the colon when identifying 'smilies'.)

Back to the "armrest". From Interim Report No.3:-

Though this has also been discussed previously, both issues are inter-related.

Lyman

It's interesting, but the fact that the cockpit remained populated in correct configuration, with pilots at the stick, and discussing other things,
may point to a lack of turbulence, or the disconnection of belts just prior to impact, something that sounds counterintuitive, but can be explained in a number of ways in connection with last second panic.

Who says the pilots died immediately? The "impact" reads as less powerful than Schiphol 737, with a better horizontal. If they survived the impact, who stays in a sinking barrel to drown? I'm off with my belts, and adios. What would Gus Grissom have done? Right....

mm43

The following Google search terms will enable you to search AF447 threads individually.

NOTE: Remove the [square brackets] and use your own search term, and there is no need to make reference to AF447, e.g.

- will return all the pages containing posts with those search terms in AF 447 Thread No.5.

- will return the pages containing posts by mm43 and/or posts mentioning mm43 in AF 447 Search to resume.

- will return the pages containing posts by mm43 only, in AF 447 Search to resume.

Use your browsers Find function and enter appropriate Search Terms to quickly locate the posts of interest on each selected page.

Finally, a search term to cover any subject on pprune will use the following:-

- and don't forget the thread search and site search functions available on pprune.

CONF iture

Infrequentflyer789,

To put things clear, I absolutely don’t 'actively dislike' the aircraft – Actually, I enjoy working on it, but I’m not blind. I have to accept I don’t know much on it. IMO Airbus made it unnecessarily complex and I’m well aware that I won’t necessarily understand what’s going on eventually and be taken by surprise.

What I do actually actively dislike and denounce, is the pseudo transparency from the BEA and justice. Why the judge refuses to include the full FDR data to the procedure ... ?

Aren’t we grown up enough to have a serious look to those data, maybe you and I are not Experts but surely they are some around here or elsewhere. It would be pure bonus for the BEA as truth is what they’re looking for ...

bubbers44

A long time ago, right after the stick, we invented the yoke. It was a big wheel like thing with no top that made it obvious what everybody was doing in the cockpit controlling the airplane. It made it simple to know what the guy on the other side of the cockpit was doing. It worked well for decades. It didn't matter much where the armrest was or if a different size person took over the seat. It was simple and self explanatory. Then a company came up with this idea they could save weight by putting this little side stick in the cockpit to do what the simple yoke system was doing. Now it isn't simple any more. Now you don't know what the other guy is doing so it is hard to respond when the airplane does something but you don't know why. Then you have laws of how all this works that some people don't understand. Now you have pilots that find themselves confused because they can't see the yoke moving any more like in the past. This is progress?

OK465

No reason to invent the wheel, fire should be enough for any caveman.

Lyman

CONFiture.

"Why does the Judge withold data from the proceeding?" Who pays her salary? Not you, not those who benefit from truth, surely?

1. Those who would be harmed by the truth,

2. Those who DO pay her salary,

3. Both.

I am happy to provide perhaps the only transparency you will "see".

philip2412

i think,the issue s/s or yoke is maybe a pschyological thing.
the yoke is something you can hold on,you can grab it with BOTH hands when in turbolence,it gives confidence b/c you are acting with your whole upper body.
you have a better feeling or the a/c b/c the motion of the yoke,the a/c and your upper body is in line.

ask yourself,who wants to drive his car with a s/s ?

jimjim1

For your info:-

mm43 said:
This seemed unlikely to me (google would surely just fix it so that it worked as expected in all three cases) so I tested the effect of prepending "www." and "http : // www." (spaces inserted to try to keep pprune happy as I seem to recall that it does not like URLs in posts) to one of the example searches. All three searches return identical looking results on the first page at least.

If this is off-topic then please feel free to delete it.

TTex600

I, for one, don't have a problem with a SS. In fact, I love the SS. But I HATE not having tactile feel of the airplane.

The Airbus forces a pilot to interact with it entirely with his eyes and ears, but that's not really the SS's fault.

Which gets me around to the topic at hand. How a qualified crew managed to totally misread/misdiagnose their situation to the point of letting it kill them and theiri passengers. I think the "eyes only" interface has something to do with it. They were first faced with conflicting visual information, and then with conflicting aural information. This may end up being nothing more than an extremely unfortunate alignment of the "holes in the cheese". The list of factors will be long.

bubbers44

Cavemen may have done much better knowing what was going on by a yoke instead of a side stick. How would you react in a Boeing at 35,000 ft if the other dude pulled the yoke all the way back and held it there for several minutes? Would you request the captain to come back to the cockpit or intervene?

CONF iture

As soon as AP did disconnect, Outer Ailerons kept the neutral position ... could it be a sign that IAS2 remained in the high speed range ?

DozyWannabe

@bubbers44 :

Much as I'd love to get back on the bit of the hamsterwheel where we're back to the ol' yoke-vs.-sidestick argument*, the fact is your hypothetical situation *did* happen, the Captain was there, and the aircraft pretty much pancaked.

Northwest Airlines Flight 6231 - Wikipedia, the free encyclopedia

[* - *Heavy* sarcastic tone implied... ]

BOAC

I would urge caution on that Wiki article "reaching a vertical acceleration of +5g" (in a spin!!??)

DozyWannabe

Page 7 of the NTSB report, (Page 10 of the PDF):

http://www.airdisaster.com/reports/ntsb/AAR75-13.pdf

So it's a peak value rather than sustained...

BOAC

A misleading term - they mean load factor not 'Vertical acceleration' aka a Spiral Dive. Not a 'spin' as per Wiki

DozyWannabe

The point is that a three-man crew including Flight Engineer on a yoke-equipped steam-gauge Boeing 727 got themselves into exactly the same mess for very similar reasons, so to claim that the presence of interlinked yokes with feedback or an old-fashioned three-man crew would definitely have solved the problem is not true. Just trying to avoid another whirl on that particular hamster wheel is all.

Turbine D

Dozy

Your quote:
IMO, you are stretching the facts to support your ongoing theme here. There are more differences, starting with the get-go, than there are similarities, although the final results were the same, if that is what you meant.

DozyWannabe

IMO that's what a die-hard yoke-plus-steam-gauge fan would say. It'd be a funny world if we were all alike.