TIGHAR

Amelia Earhart Search Forum => General discussion => Topic started by: Jeff Victor Hayden on October 06, 2013, 07:07:19 PM

Title: 2 years vs 75 years, a comparison, what can we expect?
Post by: Jeff Victor Hayden on October 06, 2013, 07:07:19 PM
It may be interesting to see how aircraft wreckage starts to deteriorate underwater as this may help in further underwater searches around Nikumaroro in the future. Here are some images from Air France flight AF-447 lost over the Atlantic Ocean on 1 June 2009. The wreckage was eventually located on 3 April 2011 and had lain on the bottom for about 2 years...

"on 3 April 2011, a team led by the Woods Hole Oceanographic Institution operating full ocean depth autonomous underwater vehicles (AUVs) owned by the Waitt Institute discovered, by means of sidescan sonar, a large portion of debris field from flight AF447.[108] Further debris and bodies, still trapped in the partly intact remains of the aircraft's fuselage, were located in water depths of between 3,800 to 4,000 metres (2,100 to 2,200 fathoms; 12,000 to 13,000 ft). The debris was found to be lying in a relatively flat and silty area of the ocean floor (as opposed to the extremely mountainous topography that was originally believed to be AF447's final resting place)"

Starting with this image of the undercarriage there are a couple of points of interest here.

1. Despite the depth of 12,000ft to 13,000ft it is interesting to note that the aircraft tyres are still in remarkable condition and can still be recognised. Yes, they look deflated and my guess is that the valves gave way first to the incredible water pressure at these depths.
2. The gear is already sinking into the "relatively flat and silty area of the ocean floor" after only 2 years.



Title: Re: 2 years vs 75 years, a comparison, what can we expect?
Post by: Chris Johnson on October 07, 2013, 01:03:33 AM
Have you got a link Jeff?
Title: Re: 2 years vs 75 years, a comparison, what can we expect?
Post by: Jeff Victor Hayden on October 07, 2013, 12:26:24 PM
Have you got a link Jeff?


http://www.airfrance447.com/ (http://www.airfrance447.com/)
Title: Re: 2 years vs 75 years, a comparison, what can we expect?
Post by: Chris Johnson on October 07, 2013, 12:37:07 PM
Thanks Jeff :)
Title: Re: 2 years vs 75 years, a comparison, what can we expect?
Post by: Jeff Victor Hayden on October 07, 2013, 02:25:22 PM
It is notable that problems with the pitot tubes on night flights cause the crews severe challenges as there are no visual references available to them to judge the attitude of the airplane in flight. So, problems with pitot tubes and darkness = trouble ahead.

Air France flight AF-447 night flight..."At 02:10:05 UTC the autopilot disengaged as did the engines' auto-thrust systems three seconds later" pitot tubes blocked with ice crystals.

AeroperĂș Flight 603 night flight... "Later investigation into the accident revealed that duct tape was accidentally left over some or all of the static ports (on the underside of the fuselage) after the aircraft was cleaned, eventually leading to the crash"

Birgenair Flight 301 night flight... "The cause was a pitot tube blocked by wasp nests that were built in it as it had been some time since the plane had been on any flights and it was not covered up properly when stored."






Title: Re: 2 years vs 75 years, a comparison, what can we expect?
Post by: Dan Swift on October 08, 2013, 03:46:30 PM
Isn't is sad how tragic some of the simplest oversights can be.  Air Florida no pitot heat on in a snow and ice storm in Washington, the ones mentioned above, a badly placed belly antenna and lack of knowledge of how to handle radio loss issues.  So simple in preparation.  So tragic when overlooked. 
Title: Re: 2 years vs 75 years, a comparison, what can we expect?
Post by: Tim Mellon on October 08, 2013, 05:40:43 PM
It is notable that problems with the pitot tubes on night flights cause the crews severe challenges as there are no visual references available to them to judge the attitude of the airplane in flight. So, problems with pitot tubes and darkness = trouble ahead.

Air France flight AF-447 night flight..."At 02:10:05 UTC the autopilot disengaged as did the engines' auto-thrust systems three seconds later" pitot tubes blocked with ice crystals.

AeroperĂș Flight 603 night flight... "Later investigation into the accident revealed that duct tape was accidentally left over some or all of the static ports (on the underside of the fuselage) after the aircraft was cleaned, eventually leading to the crash"

Birgenair Flight 301 night flight... "The cause was a pitot tube blocked by wasp nests that were built in it as it had been some time since the plane had been on any flights and it was not covered up properly when stored."

What's so hard to understand about "PREFLIGHT INSPECTION"?

Title: Re: 2 years vs 75 years, a comparison, what can we expect?
Post by: Ted G Campbell on October 08, 2013, 09:04:13 PM
Tim,
You are correct.  But did they just pull off the covers or did they actually look at the tubes?  What's on the check list as you start down the runway?
Ted Campbell