Originally Posted by IGh
AirRabbit -- that's a long one, yours in slot #71 above, you seem OK with that "alternative" standard, where operator avoids the "engines spooled-up" requirement.
Take that exemplar case noted several slots above: DEN06IA051
Those mishap pilots flew their final approach using their company's "alternative" standard -- at a "stabilized thrust" NTSB cites the EPR as steady at 1.1 EPR all the way to impact
I don’t see what would allow you to come to a conclusion that I “seem OK” with some nebulous “alternative standard.” If you read the post I made earlier, the first item I indicated as being acceptable is “Have the aircraft in the desired configuration for landing with the engines spooled and stable.” In my follow-on post (immediately above) I attempted to point out the fact that “stable thrust” doesn’t mean “not moving the throttles.” The last time I checked, an EPR reading in the neighborhood of 1.1 was very close to “idle” – and I certainly hope you don’t think that maintaining a stable, idle thrust on final is an appropriate way to get the job done!
If you are questioning the decision of the crew, who seem to have accepted what the airplane gave them, i.e., a speed, rate-of-descent, a ground track, etc, I agree with your puzzlement. Just because they maintained a “stable thrust setting” doesn’t mean that the setting they decided to use was an appropriate thrust setting – and – I’m completely in the dark about why you think I think that is OK!
In my post (immediately above) I indicated that “(the) airplane speed (must be) within the acceptable range specified in the approved operating manual used by the pilot”
…and…“(the) power setting (must be) appropriate for the landing configuration selected, and (must be) within the permissible power range for approach specified in the approved operating manual used by the pilot.”
I think for you to presume that the flight crew was flying a procedure their company mandated or approved, when they maintained essentially an idle power setting all the way down final, is a bit of a stretch. Of course without “being there,” its hard to know just what the crew was thinking … but, and excuse me if I step on some toes here, but it
seems as though the crew was deliberately attempting an “idle approach, flare, and touchdown.” I can’t imagine any company, anywhere, thinking that this is an acceptable procedure. In my opinion, this is an air-show, glitzy, "gee-wiz" stunt that has no place in air transportation service! In fact, the link you provided describes the company’s procedures as the following:
A stabilized approach means the airplane must be: at approach speed (VREF + additives); on the proper flight path at the proper sink rate, and at stabilized thrust. These requirements must be maintained throughout the rest of the approach for it to be considered a stabilized approach. If the stabilized approach requirements cannot be satisfied by the minimum stabilized approach heights or maintained throughout the rest of the approach, a go-around is required.
In my opinion, this sounds like a very logical, very safe, and completely appropriate procedure to follow. However, what the crew flew was not this procedure. Where you get the idea that the crew followed an authorized or approved “alternative” procedure is beyond my understanding.
Originally Posted by IGh
AirRabbit --
-- How does YOUR understanding of the FAA's "engine spooled-up" requirement fit with that operator's alternative "stabilized thrust"??
-- Do you think that "alternative" standard was an effective guide for those mishap-pilots??
Those mishap pilots did just what their company told them to do, at their company's "stabilized thrust". Speed control becomes quiet difficult using that "alternative" standard, when the engines took seven seconds to spool-up.
And what makes you think that this crew “did just what their company told them to do?” Do you have any statements? Any manuals? Any bulletins? Any anything? Are you of the opinion that the company lied when they supplied the definition of a “stabilized approach?”
The concept of having the engines “stabilized” within an appropriate power range to provide adequate speed and rate-of-descent … and the concept of having the engines “stabilized” at idle power … are completely different issues – and I cannot imagine that you don’t see that simple fact. I continue to puzzle over the fact that somehow you think that I believe an “alternative standard” or an “alternative procedure” is even a discussion issue here. The flight crew had an established procedure. They did not follow that procedure. That part seems pretty evident. Simply because they did not follow the established procedure, does not immediately imply that they
were complying with an acceptable or an approved “alternative procedure” – unless you have access to information that no one else has … is that the case?