Sling S-LSA vs. EAB vs. ???

[Mark Gregor]

As far as the stall speed formula it is a way to guestimate the effect. I would not count on it to be 100% accurate. I bet the it will be somewhere in the middle which is only a guess by me.

LSAs stall at such a slow speed already adding a few knots would seem to be insignificant. If the airframe is up to it wouldnt the extra wing loading allow the aircraft to actually handle better in crosswinds and landings? Just asking?

Mark

[drseti]

That RV looks beautiful. It also looks like one helluva lotta work!

[Mark Gregor]

Another thing that has not been brought up is stall warning.

What does the sling use far stall warning?
What does the Evector uses for stall warning?
What does the CT use for stall warning?
What does the sky arrow use for stall warning?
What about the citabria?

Many of these aircraft have no stall warning or not a very good one.

I have debated the need with many who say it isnt needed in such a low stall speed aircraft and a pilot would be wise to get more training before spending $ on a stall warning.
This would seem to go against what Ed has said previously. Has anyone heard of Shawn Lunt?
He was a very experienced supercub pilot who stalled it in and lost his life.
I am only a 600hr PP but I believe if 10000hr pilot with most of his time in a cub can stall it in then maybe a good stall warning might be a good idea.

All of the Tecnams I have flown have an angle of attack with a LOUD audio into the headset that WILL get your attention before approaching full stall. The AOA gives stall awareness that you will never get with a horn. After using it I am amazed it has not been accepted as the standard for all aircraft.

Mark

[drseti]

LSAs stall at such a slow speed already adding a few knots would seem to be insignificant.

Mark, when everything's going well, a few knots isn't going to make any difference at all. It's when everything's going to hell that a few knots can be the difference between death and survival. Since every accident is a chain of events, why would anyone want to deliberately forge that first link before takeoff?

[drseti]

Another thing that has not been brought up is stall warning.

What does the Evector uses for stall warning?

Mine uses the airframe buffet. Nothing else.

The AOA gives stall awareness that you will never get with a horn. After using it I am amazed it has not been accepted as the standard for all aircraft.

Very good point. An AOA indicator can certainly be a lifesaver.

[FastEddieB]

Quick post...

...my Sky Arrow uses the C-150 horn, Cessna part number and all. Anyone who's watched my videos has heard it.

I don't think my Citabrias had any stall warning beyond marked buffeting.

[cogito]

At the risk of helping lead my own thread down a rathole, this is one of my favorite clueless landing videos:

http://www.youtube.com/watch?v=5McECUtM8fw

please note the clear and loud warning alarm which starts at :30. no it's not a stall horn, but I'm sure you get my point.

(even though the video runs 4:30, the airplane is on the ground by 1:30)

[Mark Gregor]

How is it that a pilots stall it in then? Why dont they just power up when we feel the buffet and get out of the stall?

And why are we so concerned about the big danger of a situation that will change stall speed a few knots when many are flying with no stall warning whatsoever?

Feels a bit hypocritical to me like whatever I am doing is the best way ( which is typical for most pilots and I will include myself) but maybe I am missing something?

Mark

[drseti]

Mark, as that video clearly demonstrates, a loud gear-up warning horn doesn't necessarily prevent one from landing gear up. Things get even worse when the pilot is wearing an ANR headset, which (if it works properly) prevents you from hearing such annoying distractions as gear warnings and stall horns! That is why, when we do retract training, we put so much emphasis on developing the habit in the pattern of checking three times (on downwind, on base, and again on final) for those three green "down and locked" lights. (Which training this pilot obviously never received.). I've flown the Trinidad, and can assure you it does indeed have green gear-down lights, as well as a red "gear unsafe" one. So, the pilot in that video must have been both deaf and blind.

Similarly, under stress when everything else is going wrong, a pilot can very easily miss the stall warning horn. This is why we put so much training emphasis on having the student learn the exact feel of the aircraft as it approaches the stall. That buffet is pretty hard (though, admittedly, not impossible) to miss, especially if you've been trained to notice it well before the stall horn would activate. Even if you are both deaf and blind.

[drseti]

Why dont they just power up when we feel the buffet and get out of the stall?

I was remiss in not emphasizing: You don't power up to break a stall. You reduce the angle of attack. . If the stall occurs close to the ground, it takes tremendous faith, and strength of will, to push the stick forward with the earth filling the windscreen. Every instinct tells you to pull back.

Axiom: to go up, pull stick back. To go down, pull stick way back.

[jnmeade]

An AOA indicator can certainly be a lifesaver.

I agree and wish the AOA indicator on the Dynon D120 was in a better spot. I'd like to see one about at the eyebrow of the glare shield.

[jnmeade]

Since every accident is a chain of events, why would anyone want to deliberately forge that first link before takeoff?

There is a tiny but growing voice that the chain of events model of accident analysis is not useful to really figure out what when wrong and why. These voices claim it is too simplistic and tends to stop as soon as it finds someone who can be assigned responsibility.

A major proponent of this view is Prof. Nancy Leveson of MIT. You can see a study of the Cali crash for an example of a different approach.
http://sunnyday.mit.edu/

Here is a master's thesis on the Comair 5191 crash.
http://sunnyday.mit.edu/papers/nelson-thesis.pdf

[jnmeade]

I was remiss in not emphasizing: You don't power up to break a stall. You reduce the angle of attack. .

When I got typed in the Citation I, the stall recovery procedure was to advance power and hold attitude. I think the FAA may have tweaked this a little in recent years, but that is what it was 5-6 years ago.

It takes a lot of self-control to NOT push the stick forward.

[drseti]

EDIT: This is not my post but my name is on it. Wonder how that happened?

My apologies, Jim. It was my post, and my touchscreen typo. I was responding to a post of yours, and
accidentally touched "edit" instead of "quote". If you'd like, i can just go ahead and delete the whole post. Sorry!

[drseti]

When I got typed in the Citation I, the stall recovery procedure was to advance power and hold attitude.

I stand corrected. In an LSA, you break the stall by reducing angle of attack, (I've never flown the Citation I, but I suppose it's not an LSA. Just guessing...)