Thread
:
A hypothetical situation, and a doubt
View Single Post
#
2
April 9th 06, 05:47 PM posted to rec.aviation.piloting
Peter Clark
external usenet poster
Posts: n/a
A hypothetical situation, and a doubt
On 9 Apr 2006 08:38:41 -0700,
wrote:
Peter Clark wrote:
It was BA which took a 747 all the way from LAX to the UK on 3 after a
loss on takeoff just a few months ago.
Peter,
I'm neither speaking for BA nor indeed know the particulars of the
incident you mention, but if the AutoPilot had been switched on shortly
after rotation and landing gear retraction, chances are that the pilots
wouldn't even have noticed the engine loss if it occurred during the
automatic flying phase, and you'd be unnecessarily harsh on BA. Bob
Moore once related me a fascinating similar occurrence when he was PIC
and had an attractive visitor in the flight deck when one of the 4
turbines of his B-707 went blimp (albeit temporarily) and nobody in the
flight deck as much as realized it. And that wasn't even a modern-day
aircraft. Over to you, Bob
I wasn't attempting to be harsh on BA, I was just pointing out to the
poster who mentioned being onboard a turnaround in a BA 747 10+ years
ago, that they had appeared to miss reading about the incident on Feb
19 2005 where they continued on from LAX on 3 for an 11 hour flight.
Or the subsequent flight where that same aircraft lost the same engine
6 days later, 3 hours into a 14 hour leg from Hong Kong back to the UK
and continued on.
As a multi-engine pilot, I can't think of any way that you would not
know that one of the engines was failing to produce power for an
extended period of time, autopilot or not. I'm sure Bob can give
details on the 707 incident if he's interested, but even in a light
twin a temporary issue might go unobserved. However, in light twins
(piston engines) it's quite obvious when one completely stops giving
power for an extended period because the autopilot will attempt to use
ailerons to maintain heading, giving a really strange flight attitude,
and it will need to be disconnected to allow the pilot to overcome the
yaw and roll forces coming from the remaining engine while setting
rudder trim, feathering the prop, etc etc etc. If you're hand-flying
it when it stops, the need to stomp on the rudder is a quick giveaway.
As for transport category, I'm not too sure, I'd have to go play
around in a sim since I don't have a type rating yet, but in the case
of the 400 there would minimally be EICAS caution messages and the
conspicuous lack of data in one of the 4 engine readings in the upper
display. Someone more up on the type can tell us whether the yaw
dampers have enough authority to overcome the engine out issue, but
eventually they'd have to dial in rudder trim.
Specifically addressing the incident I was alluding to, they did know.
In both cases, they shut it down themselves, and I seem to recall that
for the LAX takeoff they even declared an emergency, circled for 20
minutes, and then headed out for the UK.
http://www.washingtonpost.com/wp-dyn...2005Feb28.html
http://www.post-gazette.com/pg/05061/465083.stm
http://www.usatoday.com/travel/fligh...itair-la_x.htm
http://www.iht.com/articles/2006/03/30/news/fly.php
Take care.
P
Peter Clark
View message headers