Does any 'heavy metal' use AoA gauges?
 

Hi learn'ed folk, I have seen several posts that suggest the universal panacea is to place the airplane in a pitch attitude of +15 degrees.
This is all very well if your original flight path is horizontal, but not so good if the flight path is -20 degrees or more.


Surely an Angle of Attack meter would be an asset, instead of the usual AI.


Do any large airplanes have these AoA gauges?
I think they may be fitted to some smaller executive jets.
After all the wing's Cl. is determined by AoA and not by Pitch Attitude.

Just turn the flight path vector on. Difference between pitch attitude and flightpath = AoA...

50 ton MTOW (50,000 kg) Se210 (a Grandmother of Airbus), had AoA indicator installed in cockpit.
All daughters and grand-daughters including all cousens seem not to have it installed in cockpit.

It is a user option on the 737. The military customer seem to order that option, however i haven't seen it in an airline configuration yet. The space where it would be displayed on the PFD is often used for an analog RA display.

Not quite... the is also angle of incidence of the wing to consider.

Big AoA user and "indicator" advocate here.

Military likes the display because of the operational requirements and the ability to nail approach speed/AoA after a rough calculation from the book for weight and configuration and ....

We also landed closer to the "limit" than the commercial heavies, and the nasal radiators used the "indexer" lights next to gunsight/HUD for their approaches to a rolling, pitching and short runway.

The AoA is most useful when close to max performance and landing approaches. The more current indicators ( figure 1980's and on) compensate for configuration. My first jet with a good AoA indication in the HUD did not! So one rainy night I bumped the flap lever and only had leading edge flaps down and about half the basic flaps down. So my approach speed with the "correct" AoA was about 20 knots too fast and I failed to do a good cross check of configuration and the rule of thumb approach speed. Almost slid off far end of the runway.

OTOH, the basic procedures used by the heavies in the commercial world are pretty conservative and safe. "x" degrees of pitch, and "y" amount of power will work about 99.9% of the time. Unlike AF447.

For the heavies, I would recommend a HUD with an inertial-based flight path vector and the pitch lines. AoA could be optional. Nothing like seeing where you will impact the ground/runway, huh? See Asiana crash.

A dual HUD is standard equipment on newer aircraft like the 787 and A350 onwards. On less recent ones it is optional, like the 737, CRJ and E-Jets as well as some turboprops like the Q400. Will be interesting to see if the 777NG will switch to a similar flightdeck layout to the 787.

All FBW Airbuses (A320/330/340 etc.) have an AoA display on the PFD.

Not a "standard" presentation, and not marked in units, but with 3 defined bands :ok:

More modern ones have an additional AoA display in case of loss of airspeed indication...

Concorde had a combined AoA/G indicator (vertical 'tape' instrument).

Agree cosmo...

Too many purchasers of airplanes (i.e., airlines ... and others) use the “expertise” of those they employ or others on their payroll in one manner or another. Often it is the additional expense of including a direct reading AOA indication, together with the “advice” provided by these “paid consultants” (some of whom don’t know their knee from their elbow and others often don’t want to “rock the boat) who generally advise that obtaining such an AOA indication would be “nice,” but it does cost more. Inevitably, a good share of these airplane purchasers decide to forego the “additional expense” since it would be merely “nice to have.” Anyone who has operationally flown airplanes with direct reading AOA indicators will tell you that it is a very cheap addition that provides a wealth of knowledge to the flight crews … but, unfortunately, the numbers of these folks is not growing and they are not usually in the chain of advisors.

Think about AF447, would have been the same outcome if the crew had an AoA indicator flashing and sounding? Who knows...

Cosmo / Cough. Depends which definition of alpha is in use (relative air flow to chord line only makes sense when considering isolated 2d airfoil sections). Often longitudinal axis to flight path is used for the whole aircraft and thus incidence is not a factor. In any event, target and limiting values can be expressed reference to either.

Plus, Cough, plenty of aircraft still around with no flight path vector.

PLI on ejet or even the old Avro RJ is as good as AOA. It indicates the same thing.

And a nearly a thousand where the thing is driven by air data. Yes, you heard correctly, from the air and the plumbing behind is like spaghetti. So a fault in one system drags down another. Worst of all, you can't get rid of the one that is lying. So when you really need it, you don't have it. Thank you Honeywell!

Would each aircraft, depending on loading/conditions/winds/settings, have a different AoA for the sweet spot?

Different airspeed, same AoA.

AOA on 737NG and 777. Customer option.


2500+ hrs looking at it.

Been in the cockpit of AA's 737,s. They have AoA gauges. Haven't seen them on their 757/767 fleet.

galaxy, maybe I wasnt clear..

the aircraft, at the same airspeed, will have a different AoA when heavier, than lighter...

I was also asking about landing conditions, especially weights, wont the AoA be different for the same GPA? Vref is +/-5 so there appears to be some associated AoA variable there..

I am just asking to see how many variables affect the AoA, and what is the range of the AoA as a result.