tag:www.thedonovan.com,2012://1/tag:www.thedonovan.com,2009://1.10364- 2012-01-06T18:22:36Z Comments for UPDATE: US Air 1549 We're the Military and Airpower Guys of Jonah Goldberg of National Review Online + a stray we found wandering around looking lost. All original material JHD, BHD, JR, WT, and KA 2003-2010 Movable Type 4.12 tag:www.thedonovan.com,2009://1.10364 2009-02-04T21:09:38Z 2009-02-04T22:07:13Z UPDATE: US Air 1549 Attila of Argghhh!)]]> http://www.thedonovan.com
************************************************************
NTSB ADVISORY
 ************************************************************
National Transportation Safety Board 
Washington, DC 20594
February 4, 2009
************************************************************ 

THIRD UPDATE ON INVESTIGATION INTO DITCHING OF US AIRWAYS 
JETLINER INTO HUDSON RIVER
************************************************************
The following is an update on the National Transportation
Safety Board's investigation of US Airways flight 1549, which 
ditched into the Hudson River on January 15, 2009.

The left (#1) engine, which was recovered from the Hudson 
River on January 23 and subsequently shipped to the 
manufacturer in Cincinnati where the NTSB is directing a 
teardown, was found to contain bird remains. The organic 
material found in the right (#2) engine has also been 
confirmed to be bird remains. The material from both engines 
has been sent to the Smithsonian Institution in Washington 
where the particular bird species will be identified.

As part of its investigation into this accident, the NTSB 
investigated an engine surge event that occurred in the right 
(#2) engine during a flight on January 13, two days prior to 
the accident. The engine recovered from the surge and the 
remainder of the flight was completed uneventfully. The NTSB 
determined that the surge was due to a faulty temperature 
sensor, which was replaced by maintenance personal following 
approved procedures. After the engine was examined with a 
boroscope and found to be undamaged and in good working 
order, the aircraft was returned to service.
On December 31, 2008, the Federal Aviation Administration 
(FAA) issued an Airworthiness Directive (AD) covering all 
CFM56-5B series turbofan engines, the same type that was on 
the accident aircraft. After examining the engine maintenance 
records and interviewing relevant personnel, the NTSB 
determined that all of the requirements of the AD were 
complied with prior to the accident flight.

During the accident flight, the flight data recorder revealed
no anomalies or malfunctions in either engine up to the point 
where the captain reported a bird strike, after which there 
was an uncommanded loss of thrust in both engines.

Last week the aircraft was moved from the barge where it had 
been docked in Jersey City, NJ, to a secure salvage yard in 
Kearny, NJ, where it will remain throughout the NTSB 
investigation, which is expected to last 12-18 months.

Photo of feather found in the left (#1) engine

 NTSB Media Contact: Peter Knudson 
(202) 314-6100 
peter.knudson@ntsb.gov
Now, a couple of points:

- I seem to remember Bill O'Reilly starting to go into high dudgeon about the engines, i.e., he was going to get to the bottom of this vis-a-vis these (potentially) GE pieces of crap if that's what caused the jet to turn into an expensive French glider. I paraphrase of course, but that was my impression from catching snippets of his show shortly after the incident.

From reading the third and fourth paragraphs, this does not seem to be the case. First, the 13 January surge well before the day of the accident caused by a sensor failure is not a terribly unusual event...sensors fail and engines sometimes get goofy as a result; they won't explode and the worst case is usually an uncommanded shutdown.

This sounds scary but it's nowhere near the crisis of a complete thrust loss due to bird ingestion. In fact, I'm MUCH more afraid of the latter than I am of the former (and I do this for a living).

Second, the boroscope inspection is quite thorough...one blade at a time with a powerful light and something that resembles what they use on you in a colonoscopy. Third, US Air had complied with a directive for inspecting the engines...if the NTSB says so, I believe 'em, 'cause their investigations are fully open to the public and the press and their teams are shadowed by both reporters and lawyers. They would NOT cover this up (despite what Kos or Rosie O'Donnell might think) because of the way their process is designed.

- Taking off out of La Guardia SUCKS. Not only is the traffic congestion monumental and the radios jammed with Ground, Tower, Departure, et al., sitting in the departure position waiting for clearance to roll is an exercise in Hope and Change, as in

"I HOPE those *&!#&$!! birds I see off the end of the runway CHANGE their *&!#&$!!-ing flight path before I get there."

Many a pilot has hit birds and none of us like it, but there are birds and there are birds. Canadian geese are the avian equivalent of cannon balls...big, heavy and dense. Perfect engine trashers. NOTE: testing has shown that chickens and sparrows are mere trifles to most of the larger jet engines...pigeons, on the other hand are like little cannon balls--small, heavy and dense...and hell on engines.

So, Sully hit what is probably the biggest threat in the New York bird migration pantheon. He went through so many so suddenly that NO motor would have come out of this unscathed and frankly I'm surprised there wasn't a bigger "bang" after impact from internal damage, i.e., a fire or fires from broken fuel lines, ruptured flight control lines, etc. In fact, thank God none of them hit the windscreen dead on. Guys have died from getting turkey buzzards in the face (literally) so the fact that the cockpit was complete;y missed was a very good thing. At departure speeds, I doubt even a Canadian goose would have penetrated the flight deck but at least he didn't have the distraction of a major splatter on the window.

-Finally, NTSB reports take forever, thanks to the "openness" framework. Openness is great if you want to assign blame, which is what the NTSB does, basically, after reconstructing the chain of events after the accident based on evidence available. That's why there's about 100 lawyers in the back of the room when the Board briefs...and a massive use of cell phones to law firms after that to lay litigation groundwork. Of course, this does very little to prevent accidents because most surviving crew members won't say squat to anybody without their own legal counsel and union reps present, and then they'll say very little.

The media O'Reillys and the Dewey, Cheatum and Howe legal beagles of the world are looking for scalps. That's one reason I miss the USAF's Mishap Investigation Boards (as opposed to the NTSB-like Accident Board that follows). Nothing said in the former could be used against a witness for punitive purposes. The objective was determining cause and implementing preventive measures in future operations...and why a full report could be generated 30 DAYS after the MIB convened. But I digress...

What Captain Sullenberger did was amazing. CIrcumstances were such that he was able to apply his superior skills and judgement to great effect. This was truly one for the history books and I mean that literally. There was no mystery to why he had to land earlier than he originally planned...he hit a bunch of big-ass birds that trashed his thrusters and left him with zero options. Nothing to suspect here...lots to praise and be grateful for. -Attila]]> tag:www.thedonovan.com,2009://1.10364-comment:83935 Comment from J.M. Heinrichs on 2009-02-05 J.M. Heinrichs
The screens were primarily intended to prevent FOAD from Russian runways and probably not sized to counter geese. The FOAD would have been thrown up by the nosewheel, and thus the screens closed the inlet when the wheel was on the ground. Apparently the transition from ducts closed to ducts open had little effect on the takeoff as sensed by the pilot. From the exterior observer, the operation was very quick.

No, the screen would not stop a goose.

Cheers]]> 2009-02-05T23:06:32Z 2009-02-05T23:06:32Z tag:www.thedonovan.com,2009://1.10364-comment:83919 Comment from Josh on 2009-02-05 Josh
Maybe we just need to paint the airplanes to look like birds of prey, like those hawk sillhouettes you're supposed to put on picture windows to keep the birds from smacking into them...
]]> 2009-02-05T18:17:22Z 2009-02-05T18:17:22Z tag:www.thedonovan.com,2009://1.10364-comment:83904 Comment from John of Argghhh! on 2009-02-05 John of Argghhh! http://www.thedonovan.com
I was thinking more along the lines of "Redneck Airways..."]]> 2009-02-05T15:29:50Z 2009-02-05T15:29:50Z tag:www.thedonovan.com,2009://1.10364-comment:83901 Comment from Attila of Argghhh! on 2009-02-05 Attila of Argghhh! http://www.thedonovan.com
Two words vis-a-vis deer sirens: "Doppler effect."

NDSteve,

My huntin' friends tell me a goose makes a hell of a "thump" when they hit the deck after taking on excessive buckshot. The swans may be bigger, but the geese are WAY big enough to hammer an engine. (US1549=QED).]]> 2009-02-05T15:01:15Z 2009-02-05T15:01:15Z tag:www.thedonovan.com,2009://1.10364-comment:83900 Comment from fdcol63 on 2009-02-05 fdcol63 Never mind .... just read Josh's comments and the responses more carefully. Sorry. 2009-02-05T14:41:52Z 2009-02-05T14:41:52Z tag:www.thedonovan.com,2009://1.10364-comment:83899 Comment from fdcol63 on 2009-02-05 fdcol63 Would some kind of wire mesh over the air intakes create so much drag, reduce lift, or otherwise alter flight characteristics to make that idea unfeasable? 2009-02-05T14:38:29Z 2009-02-05T14:38:29Z tag:www.thedonovan.com,2009://1.10364-comment:83898 Comment from NevadaDailySteve on 2009-02-05 NevadaDailySteve
Bill O'Reilly has a problem, he gets an idea in his head and you can't knock it out with a baseball bat. Now, sometimes that's a good thing but not always. O'Reilly has a vendetta againist GE and its chairman Jeffrey Immelt and anything he can pelt them with he will.

As for geese, they're small potatoes. there is a small lake (pond really, but the city owns it so it's a lake) here where geese always stop by and they are sometimes joined by trumpeter swans. I went out and took a picture there last week and I was struck by how much larger the swans were than the geese. 

http://www.nevadadailymail.com/story/1497790.html

BTW my dad had a saying about cr*p through a goose and I never understood why their digestive systems would be any speedier than any others but after seeing all those geese I can at least attest to the AMOUNT they produce.

]]> 2009-02-05T14:21:30Z 2009-02-05T14:21:30Z tag:www.thedonovan.com,2009://1.10364-comment:83897 Comment from BillT on 2009-02-05 BillT http://www.thedonovan.com
Turkey buzzards are the worst. They barf when they think they're being threatened, and remember what they *eat*...
]]> 2009-02-05T13:57:51Z 2009-02-05T13:57:51Z tag:www.thedonovan.com,2009://1.10364-comment:83895 Comment from John of Argghhh! on 2009-02-05 John of Argghhh! http://www.thedonovan.com 2009-02-05T12:54:44Z 2009-02-05T12:54:44Z tag:www.thedonovan.com,2009://1.10364-comment:83893 Comment from Argent on 2009-02-05 Argent http://www.aaronpoeze.com
Can something be mounted on an aircraft to get these birds out of the way one way or the other?  Is it worth it to do that?  If it's really good it can pluck them and serve in flight. :D

Litigation really is the paralysis of our modern society.
]]> 2009-02-05T08:42:01Z 2009-02-05T08:42:01Z tag:www.thedonovan.com,2009://1.10364-comment:83890 Comment from Josh on 2009-02-05 Josh Anything big and heavy enough to be useful to deflect a flock of 4-lb geese is going to significantly impede airflow into the engine, Josh. The device would have to span two metres wide, with small enough apertures to screen or mash the incoming birds, and yet big enough holes to allow the engine to operate at a reasonable level of efficiency. And it must never shed parts of itself into the engine, either.

Hmmm the high-bypass turbofans popular these days certainly DO make it more of a problem.  What happened to the good old days with those good old noisy, smoky turbojets?

Plus the thing would be a magnet for ice, so it would have to be heated, and preheating air going into the engine also reduces its performance.

If it were in fact some kind of device utilizing metal cables, maybe you could just run electrical current right through them?  That wouldn't affect performance nearly as much as blowing hot bleed air all over them.

Personally I think the effort would be best invested in small chemical lasers to shoot the bastards down before they can get ingested. They are always flying without transponders and refusing ATC vectors anyway. Somebody ought to pull their ticket.

Damn straight!  But instead of lasers, why not mount a bunch of tiny little 3 inch long miniature AIM-9s by each engine?

]]> 2009-02-05T07:35:58Z 2009-02-05T07:35:58Z tag:www.thedonovan.com,2009://1.10364-comment:83887 Comment from Josh on 2009-02-05 Josh All my engineer buddies tell me stuff in front of the intake is basically a Bad Thing, regardless of its relative "density."

I'd tell ya that too, but then again, we'll also tell you that engineering is often a tradeoff between one Bad Thing or another.

As far as shock waves go, not that big a deal on something as slow as a commercial jet. [...] Ironically, being slow requires MORE power than at cruise so any obstruction to flow, no matter how minor, comes at great cost.

Yeah in this particular case I guess the shockwaves aren't really the issue so much as the problems with drag and turbulence on the airflow (since you want smooth airflow into the intake), although airspeed is more important here than engine power.

but anything in front of that big hole is looked on with extreme suspicion by engineer and pilot alike

Certainly true, which is why it's vital that any device be designed so that it's only "in front of the hole" on takeoff (and maybe landing), and then gets out of the way.

]]> 2009-02-05T06:50:40Z 2009-02-05T06:50:40Z tag:www.thedonovan.com,2009://1.10364-comment:83886 Comment from Chris Taylor on 2009-02-05 Chris Taylor http://taylor.typepad.com
Plus the thing would be a magnet for ice, so it would have to be heated, and preheating air going into the engine also reduces its performance.

Personally I think the effort would be best invested in small chemical lasers to shoot the bastards down before they can get ingested.  They are always flying without transponders and refusing ATC vectors anyway.  Somebody ought to pull their ticket.
]]> 2009-02-05T06:50:17Z 2009-02-05T06:50:17Z tag:www.thedonovan.com,2009://1.10364-comment:83885 Comment from Attila of Argghhh! on 2009-02-05 Attila of Argghhh! http://www.thedonovan.com
All my engineer buddies tell me stuff in front of the intake is basically a Bad Thing, regardless of its relative "density."

As far as shock waves go, not that big a deal on something as slow as a commercial jet. "Slow" is relative, but a 'Bus motors around at something like .78 Mach and very much slower in the departure/arrival pattern (I know...they force me to slow down in the pattern all the time). Ironically, being slow requires MORE power than at cruise so any obstruction to flow, no matter how minor, comes at great cost. 

Now, if we're talking Mach 3+, or even transonic/low supersonic, yeah, now you're getting into variable geometry intake ramps (F-15) and/or shock cones (SR-71). Take a close look at the spinners on a commercial jet next time you get a chance...not much "pointyness" there 'cause it isn't necessary, but anything in front of that big hole is looked on with extreme suspicion by engineer and pilot alike.]]> 2009-02-05T06:32:08Z 2009-02-05T06:32:08Z tag:www.thedonovan.com,2009://1.10364-comment:83877 Comment from Josh on 2009-02-04 Josh
I guess my basic idea I'm trying to describe is not "armor" so much as an attempt to deploy some sort of "screen"-like device over the intake that, at relatively low velocities, where air can be approximated as an extremely low-viscosity fluid (unlike cruising velocities, where air begins to approximate a high-viscosity fluid, AND you get into problems with shockwaves and such), will not significantly hinder airflow, while at the same time (mostly depending on collision speed), either deflecting or "chopping up" any flying animals or other objects that might be in the air (stray parachuters, weather balloons, whatever) before they hit the turbine blades.  It's not so much an apparatus to completely shield the intake, as that would be incompatible with achieving takeoff thrust, as it is an attempt to mitigate the damage of a birdstrike or something like that.
]]> 2009-02-05T04:14:17Z 2009-02-05T04:14:17Z tag:www.thedonovan.com,2009://1.10364-comment:83874 Comment from Justthisguy on 2009-02-04 Justthisguy http://enemiesofthelibrary.blogspot.com In one sentence, the cause was enemy action by illegal-immigrant Canadian terrorists. I have been trying for some time to get my (probably ex-by-now) Sweety to stop feeding the damned Canada geese which hang out at the pond on her property. They crowd out the native Georgia birds, crap everywhere, and just won't shut up. Every time I suggested that she had them tame enough that we could get them dead and into the oven without making shotgun noises, she looked at me all funny-like. 2009-02-05T02:45:47Z 2009-02-05T02:45:47Z tag:www.thedonovan.com,2009://1.10364-comment:83866 Comment from Attila of Argghhh! on 2009-02-04 Attila of Argghhh! http://www.thedonovan.com
Alas, the mass flow requirement for today's commercial engines is too great to allow for "armor" in front of the intakes for takeoff. 

Granted, there have been designs like the one you refer to but they were conceived for scenarios commercial jets would never face, like landing on/taking off from unimproved fields. Also, I'm not so sure the MiG or Sukhoi designs were more than a "good idea." If I remember correctly, the main intake opens during takeoff on nose strut extension (I think) and closes on main gear touchdown on landing and dorsal intake opens above the now-closed primary intake while the latter is closed. Even a Russian fighter, with its HUGE brute-force engineered stainless steel engines-from-hell would have major problems with thrust requirements on takeoff with this configuration because those requirements would dwarf anything required when recovering. The departing jet is loaded for combat (fuel, ordnance, etc.) and it is trying to overcome gravity, not using it to return to earth at relatively low power settings.

Finally, the bird strike risk does not overshadow the loss-of-thrust risk imposed by a however-temporary obstruction over the intake. Then there's ice buildup on something like that on a winter day while taxiing to the runway, etc., etc., etc.

In short, it sounds good, but it's way too impractical.]]> 2009-02-04T23:17:34Z 2009-02-04T23:17:34Z tag:www.thedonovan.com,2009://1.10364-comment:83864 Comment from Josh on 2009-02-04 Josh
This does make me wonder, though...could there be some way to fit podded turbofans with some kind of anti-FOD device for takeoffs and landings?  I mean the MiG-29 has some kind of variable-geometry intake nacelles that change the airflow pattern for takeoffs on unimproved airstrips to avoid ingestion of crap on the ground, although I don't know if it helps any for avoiding birdstrikes, and the engine layout is very different, as they're buried in those under-fuselage nacelles.

I'm thinking maybe some kind of system with wires set into the outer rim of the intake, with one end of each wire fixed and the other on a little roller, so they make a web pattern when extended and then at a few thousand feet the pilot hits the switch and they retract back into the rim...
]]> 2009-02-04T22:43:04Z 2009-02-04T22:43:04Z