Midair over Senegal

[allardjd 1,853]

This is kind of a late breaker - supposedly happened on the 5th... bizarre story.

 

Supposedly a B737 airliner and an HS-125 air ambulance made contact at FL350 over Senegal.  The 737 landed safely with wing damage consistent with striking another aircraft.  The HS-125 continued out over the Atlantic and disappeared.  It is suspected that the collision caused a depressurization in the HS-125 and incapacitated all aboard, so it continued on autopilot until the fuel was exhausted.  

 

It sounds like only a glancing blow but enough to seal the fate of those aboard the ambulance flight, apparently. Sad story but could have been worse if both AC had gone down.

 

John

 

http://www.avherald.com/h?article=48c031e2&opt=0

[Bruce (a.k.a. brian747) 142]

Thank you for that, John, I hadn't seen any references to the incident previously.

 

It does sound grim for the ambulance flight, indeed. Our thoughts go out to the families of the seven who were (we have to presume) lost.

 

The circumstances are unpleasantly reminiscent of the depressurisation problem that killed everyone on board the ill-fated flight of the golfer Payne Stewart in 1999, except in that case it was a flight from Florida to Texas, and no other aircraft was involved. However the military pilots who chased the Learjet reported the presence of frost or condensation covering most of the windshield, hence depressurisation was confirmed to have occurred. (The aircraft subsequently crashed in South Dakota when it ran out of fuel).

 

B.

 

[brett 2,283]

With all the rules in aviation today you would think we would have seen and end to senseless tragedies like this. A sad ending to a lifesaving aircraft, my thoughts and prayers go out to those lost and injured. 

[Captain Coffee 2,030]

Weird one...a crash and someone only heard something "funny", not a "Huge BANG"...also weird that possibly one or both didn't have transponders set to provide alerts, or possibly not on?

 

Also the "closing" was apparently somewhat head on, but both are at 35,000, neither at a 34,500 or 35,500...isn't that standard for one direction or another to be at a not quite "even" altitude?

I am suspecting someone was flying "Casual" with regards to procedures/equipment?

 

When I sim, I usually set the altitude to something odd like 10300, especially if I am Autopiloting/Oblivious/Cooking Dinner...most AI fly at even altitudes, so it is easy to avoid collisions with Computer pilots...not so easy with RL pilots perhaps.

 

Thoughts with the families of those lost.

[allardjd 1,853]

I think at those altitudes, they are required to be IFR and therefore altitudes are per the approved flight plan and ATC instructions.  If operating on an IFR flight plan as they almost had to be, the controller has the primary responsibility for AC separation, though if in VMC conditions, the aircrew are also expected to make an effort to "see and avoid".  Not all that easy at those closure rates.  I think the controllers are complicit here, unless they were outside radar coverage, and maybe even then.

 

All that even and odd altitude stuff mostly comes into play in the flight planning and for uncontrolled flights. If zig-zagging along a line of VORs crosses you from one sector to another and back again, surely you are not required or requested to go up or down a thousand feet each time that happens.  I believe those "rules" are more guidelines and take a back seat to practicality and to ATC.

 

I understand some places use a "quadrantal"  rule with 90 degree segments separated by altitude but in the usual 180 degree segments, one shouldn't take too much comfort in the separation provided.  You could have two aircraft, both flying at the "legal" height on headings 179 degrees apart, so virtually head on.

 

I don't know if they were within radar coverage or not, but if so, why didn't ATC warn one or the other or both?  Also wonder about TCAS but we have to remember it's third world and maybe what's required here is not mandatory there.  Maybe they didn't have it, or it wasn't working or they ignored it or turned it off.   

 

John

[hurricanemk1c 195]

Reminds me of the ERJ-135 and 737-800 collision over Brazil (http://aviation-safety.net/database/record.php?id=20060929-1). In that case TCAS was accidently turned off by the crew of the Embraer due to a poor design.

 

Sad to hear about the loss of the HS-125 there. Especially because of what it was carrying

[allardjd 1,853]

@ Chuck - very similar case, and the responsibility/culpability of the Brazilian ATC (invariably the military in Brazil) was whitewashed with the blame laid on the bizjet.  TCAS does not absolve ATC of their responsibility for maintaining separation of aircraft that are IFR.  

 

The most significant difference in the two accidents is that in Senegal, the airliner was the surviving aircraft; in Brazil the 737 went down and the bizjet survived.

 

There was one over the ocean off Africa a while back too, both large planes, one a military transport, as I recall but don't have the details.  Will look.

 

John

 

EDIT:

 

Good account of it here...

 

http://www.c141heaven.info/dotcom/65/pic_65_9405.php

 

Both military transports, one US, one German.

[britfrog 180]

T I A

[allardjd 1,853]

T I A

 

 

Indeed it is...

 

John

[SEATAC 400]

Wow! Weird and sad story