Because all these keyboard dimwits want to try and prove how much smarter they are from everybody else. Instead they just prove what dolts they are.

 

Sink r8,

I'm guessing I am the sky-genii !!! I actually like that better than some of the other things I've been called on APC.

I think I understand the intent of your post...thou shalt not land over Max Demonstrated Crosswind Component. With that said, if your FAA Approved AOM specifies (a conservative) crosswind limit than it is just that, a limitation.

Many aircraft have autoland wind limitations..they are just that: limitations. The spirit of these are, the airplane is low to the ground, visibility is near zero at best and the amount of "wiggle room" is marginal. Thus the manufacturer has come up with hard and fast limitations. These values are usually attained in the simulator, not the airplane. Max Crosswind Limitations (keyword limitation) is a value also usually attained in the simulator because Mother Nature is hard to predict. Finally, in Part 25 Certification of US-manufacturered jets, gust values are only vaguely mentioned. Our European rivals (Airbus and Fokker) do address gust values in their certification process.

Back to Max Demonstrated Crosswind Component:

Under FAR Part 25 aircraft are tested to a"demonstrated" maximum crosswind as part of their certification. In essence this is the highest crosswinds the aircraft flew in during testing on that day, given the manufacturer's best attempt to have mother Nature provide crosswinds.

That value means the test pilot was able to satisfactorily handle the aircraft using normal technique and strength.

A demonstrated parameter is not a design maximum- like an MMO speed for instance, which if exceeded, may result in loss of the aircraft-but the maximum at which the aircraft was tested to.
The manufacturers and the FAA are very careful with this distinction. It means that the aircraft can conceivably operate in higher crosswinds, but there is no data to say how safe it is one way or the other.

Sink, what I think you mean, is that even though this 29 knot or 30 knot value is a demonstrated value, landing above it opens a can of worms thus making it a limiting value for liability purposes. I can agree with that. My analogy is being invited to the Chief Pilot's luncheon without the place setting.

What AA73 (I think is trying to say) is the Capt was justified in his choice to abandon the approach and if not given a runway aligned with the wind or at least within the Capts comfort zone it would ultimately result in declaring an emergency to safely land at JFK given the local controllers wind advisory.

I mostly agree with that also.

What baffles many is that the pilot not flying responded with we cant land on 22R, if we cant get 31R we will declare an emergency...ok. Maybe not how I would handle it, but not going to Monday morning Quarterback it. Here's my sticking point. AA2 advised tower of intentions. Tower gave runway heading and then asked to clarify, basically did I understand you correctly. AA 2 then chastized the controller and broke off into their traffic pattern.

I'll leave it at that. I think until the people that sign our certificates and others that review this kind of stuff come out with findings...I think this issue has been beaten to a pulp.

Signed,
The Sky Genii !!!

 

As he hits his 336th post.

If speculation isn't your thing, you're (sorry: "your") in the wrong place.

 

There must be at least two of you to make sky-genii. You're a single sky-genius.

I don't really care too much about this debate, in the sense that every crew makes individual decisions about what to accept, or what to refuse. In my opinion, if you're doing something tougher than the Boeing test pilots and engineers put in the book, you should do it with a good reason.

I only got into this discussion because I am familiar with a crew that found out the hard way that "declaring" doesn't trump all the cards that the FAA has in their hand. The deck is stacked, and it is a costly experience to try to extricate oneself from the game, once the Feds decide they must not lose. And, for reasons that are not entirely clear to me, they really, really, really hate to lose even on a two-week suspension. Which is why I added to the discussion the notion that the actual block-in fuel will get just a leeeetle bit more scrutiny than normal in this case. I don't have any interest in discussing the wind/runway: if they felt they had to have 31R, I don't question their judgment.

Regards,

Sink r8

 

Bingo!

Agreed, it's been beaten to a pulp. I guess we'll all find out the rest of the details if/when the rest of it becomes public. Just glad it didn't turn into even more of an emergency.

 

Just an informational post

>Crosswind Demonstration.

A 90-degree crosswind component at 10 meters of at least 20 knots or 0.2 VS0, whichever is greater, except that it need not exceed 25 knots, must be demonstrated during type certification tests.

There are two results possible:
• A crosswind component value may be established which meets the minimum requirements but is not considered to be a limiting value for aircraft handling
characteristics. This "demonstrated" value should be included as information in the Aircraft Flight Manual.

•A crosswind component value may be established which is considered to be a maximum limiting value up to which it is safe to operate for takeoff and landing. This "limiting" value should be shown in the Operating Limitations section of the AFM.

According to the Flight Test Guide there are two possibilities on how to note crosswinds in the Aircraft Flight Manual AFM.1 If the demonstrated crosswind is not considered to be a limiting value for aircraft handling characteristics, this demonstrated value can be placed as information in the AFM. Higher crosswinds are then allowed when the applicable operational requirements and the airline specification allow it. For instance, the AFM of the B737-400 states the following on crosswind “The maximum demonstrated crosswind component for takeoff and landing is 35 knots reported wind at 10 meter height. This component is not considered to be limiting on a dry runway with all engines operating”.

Does this mean that there is no limit for this aircraft? No.<

 

In the interest of intellectual honesty, there is a glitch with my suggestion that this "case", if the FAA pressed-to-test, would hinge on the actual block-in fuel. I received a little more info on te similar case to which I referred. Contrary to what I thought, the case the government chose had nothing to do with emergency authority, or block-in fuel. That is to say the trigger for the violation was a vindictive controller writing up the crew for declaring an emergency when they were not getting answers from him on getting back to field. The actual charge was something the Feds dreamt up, using the flight plan, based on a flawed interpretation of a minor secondary point. IOW, they could not successfully go after the crew for the source of their ire, and fuel at block-in could not be used, so they found something else.

In the case of American 2, I see no evidence the controllers are being vindictive (witness their press release), but I certainly get the vibe they are not happy about having to issue clearances on 22L when the winds favor 31R. Maybe they're under some unde pressure, and so maybe the FAA will not want to push the issue?

So, while you can't predict whether the FAA might push the issue, and while I have some reservations about the speed and manner in which the crew forced the timing of their landing (not the runway they demanded), I doubt the actual block-in fuel would be the kind of earth-shattering revelation that I suggested.

 

Makes perfect sense. The only question is the venue in which you're discussing this. In the crew lounge, or in the cockpit, we can see this one way. If you end up going off the side, and someone gets hurt, your career path will probably go through a court of law, where this discussion would take up several days. And the plaintiff's attorneys would raise his/her eyebrows, and put on a deeply skeptical face, as you try to explain why it's not a limitation.

It's unfortunate that we have to think this way, but our world is not just stick-and-rudder. So my philosophy is that I might exceed max demonstarted crosswind component for a very good reason (which may simply be that there was no alternative runway). Failing to demand the better runway is not a very good reason, in my opinion.

OK, enough on this thread for me.

 

I think one thing to take away from this incident is the fact that ALL of us, Pilots and Controllers alike, need to be using established reporting systems to report safety issues (or perceived safety issues).

For those of you who don't have intimate experience with the ASAP program, those reports do get read, and action does result from them. Same thing for NASA reports.

If all of a sudden two hundred pilots and forty controllers expressed their concerns that safety was being jeopardized by prioritizing flow and traffic volume over safe operations, it will correct the issue. (The last thing that any airline/FAA manager wants is a paper trail showing that they ignored direct input from end user operators about a safety issue).

Bottom line is this: Work with the system, but also work within the system. If you feel as a crewmember that something is unsafe, then take corrective actions (up to and including appropriate use of PIC authority). But also make every effort to affort reasonable consideration and advance notice to the other users of the system, including the controllers that are busting $@@ every day to get the job done.

 

Thread revival...

What was the outcome of this incident?