Wednesday, August 14, 2013

Aviation Update

Regards the UPS 1354 crash, condolences to the families of the victims and to the UPS family in general, who've now suffered the loss of four crewmembers and two beautiful airplanes in the last three years.

A couple of observations.

As with the Asiana crash, the NTSB has been very proactive and transparent so far.  They appear to be trying to do everything possible to remove the bad taste left by the recent reemergence of TWA800 story.  This is a good thing.

The weather could have been a factor, but that doesn't appear likely.  The ceiling and visibility was well above the minimums for runway 18, and from all we know the PAPI guidance lights were functional.  There is no instrument landing system for that approach.  One of the main questions they will likely be asking is why flight 1354--an Airbus widebody (a "heavy" in ATC lingo)--was shooting an approach on runway 18 instead of runway 06 or 24, which is about 3000 feet longer and has an ILS.  The CVR and ATC tapes will likely answer that question relatively soon. 

Witness statements are important as well--NTSB says they are on scene to collect 'perishable' info such as that from ear and eyewitnesses--and most have agreed there were explosions, although the number seems to range from 2 to 5.  As the fire department said, those could have been triggered by fuel tank impact.

As to witnesses, one man claimed to have been awakened by the explosions and taken his dog out for a walk to see what was going on and told of two explosions. Hearing several explosions could be explained by the aircraft initially striking the side of the small hill, first explosion, separating, then the remainder cartwheeling and coming to rest and exploding again. There are pictures of what appears to be the vertical stabilizer intact in the wreckage so the age-old issue of Airbuses and their tail sections might not have been a factor. Additionally it appears the aircraft was in a very shallow descent when it hit, which suggests they had some control (which would suggest the aircraft was physically intact--for the most part at least).

Interestingly, some published witness statements tend to become perishable themselves after crashes, we'll see if it happens on this one.  The same guy quoted above, Eddie Smith, was also quoted as follows in early editions regards his dog walk:
Smith said he was stopped by a Birmingham police officer who drew his weapon and ordered him to return to his home and said that there had been a plane crash.
Assuming he wasn't embellishing, why would a police officer draw a weapon on a guy walking his dog just because a plane had crashed?

Other witnesses claimed to hear strange engine noises and that the plane was on fire before it hit the ground.
Eye witnesses reported that the aircraft engines sounded odd and that the twin engine plane was on fire before it hit the ground.
Those things could be explained by the plane catching fire after initial impact with the trees and the pilot trying to apply power causing the engines to spool up as they realized they were too low.  There's a lag between the time a pilot firewalls the throttle and the engines respond, which is troublesome when the aircraft is too close to the ground.  However, if the witnesses are correct that the aircraft was on fire before striking anything it might change the entire investigation. As Al.com admitted regarding the crash of UPS flight 6 in Dubai a few years ago...
Al Qaeda claimed responsibility for the attack, but there is no evidence to support their claim.
Indeed they did.  And of course we just came off a huge worldwide terror alert centered around AQAP, who were the ones that placed cargo bombs on two aircraft during that same time period several years ago.  So pretending there's no possible terrorism concern would be foolish.  However, there are many things that could rule it out pretty quickly, perhaps the most obvious being why they were landing on that specific runway in the dark.  Reports say the crew issued no distress call, suggesting they didn't know they had a problem until it was too late.

UPDATE  8/15/13

Here's the second press conference on the crash..


Two questions have possibly been answered.  One, it appears runway 06-24 was closed for repairs when this aircraft arrived.  This explains why the flight was landing on the shorter north-south runway without an ILS.  Runway 18 was the natural choice as compared to runway 36 based on light winds and the fact the flight was arriving from the north during a low traffic time.  An ever so slight tailwind of around 5 mph was reported but should not have seriously affected the approach, however the aircraft did pass through some shower activity from about 5 to 30 miles north of the airport during descent.  Flightaware profiles show the jet descended pretty rapidly through the area on its way in, but again, the crew didn't report anything unusual. 

Two, according to the NTSB's engine experts there was no evidence of a pre-impact fire. This does not mean the plane wasn't on fire before impact, just that the engines likely were not.  Also, no evidence of an uncontained engine failure to explain the short landing.  Recall several witnesses said the engines didn't sound quite right.   Former NTSB expert John Goglia has also been quoted as saying the engine turbofan blades were probably not spinning as fast as they normally would be in 'flight idle' (common to most landings) because they were still intact after impact.  This could explain the sounds people heard.  A lot will become more clear when they analyze the FDR, which is now back at NTSB headquarters.

1 comment:

Right Truth said...

I've been gone all day on a motorcycle trip with my hubby, no news. I did hear one witness say it sounded like a sonic boom and I got the impression this sound was BEFORE the plane crashed into the air. Which makes me wonder. Al-Qaeda loves taking down airplanes....

Debbie
Right Truth
http://www.righttruth.typepad.com