Captain a écrit:
Citation:
On sait maintenant qu'aucun pilote de ligne du monde, dans aucune compagnie du monde, n'avait été (avant cet accident ) entrainé au pilotage manuel en loi Alternate a haute altitude, donc soyons tres modestes.....
Tout ca pour dire que comprendre que telle vitesse etait valide a tel moment, comment ne l'on t-ils pas vu?, c'est tres facile quand on a les bandes et qu'on est assis derriere un bureau sans pression temporelle.....
c'est ce que certains ,qui vont se reconnaître , devraient réciter ...20 fois ...chaque matin en se levant !
Il me semble utile de rappeler cet incident de NW 98 survenu 22 jours après l’accident de l’AF447 :
http://www.flyertalk.com/forum/northwes ... ailed.htmlJun 26, 09, 4:18 pm #2
dusdidt
Join Date: Feb 2005
Location: NYC
Programs: Gold Medallion
Posts: 169
On June 23, Airbus 330, flight NW98's speed sensors and autopilot failed On Tuesday, June 23, NW98, an Airbus 330 flying from Hong Kong to Tokyo encountered icy rain and then its speed sensors and autopilot system failed. This possibly was the icing problem with th Thales pitot speed sensors on the AF 447, causing it to go down in the Atlantic off of Brazil. NW and Delta also have Thales pitot speed sensors on their A330 and A320 metal and have said they are in the process of replacing Thales pitot with another manufacturer's Pitot.
My question is did the NW 98 Airbus still have Thales speed sensors? Is NW and Delta still flying Airbus metal with these Thales pitot which Airbus advised in 2007 that airlines should replace in A320s in 2007 and in A330 in 2008?
A TAM Airlines Airbus 330 also had the same problem happen on May 21 flying from Miami to Sao Paulo.
Here is the NW pilot's testimony of what happened.Citation:
"Tuesday 23rd June, 2009 10am enroute HKG to NRT. Entering Narita Japan airspace.
"FL390 mostly clear with occasional isolated areas of rain, clouds tops about FL410.
"Outside air temperature was -50C TAT -21C (you're not supposed to get liquid water at these temps). We did.
"As we were following other aircraft along our route. We approached a large area of rain below us. Tilting the weather radar down we could see the heavy rain below, displayed in red. At our altitude the radar indicated green or light precipitation, most likely ice crystals we thought.
"Entering the cloud tops we experienced just light to moderate turbulence. (The winds were around 30kts at altitude.) After about 15 seconds we encountered moderate rain. We thought it odd to have rain streaming up the windshield at this altitude and the sound of the plane getting pelted like an aluminum garage door. It got very warm and humid in the cockpit all of a sudden.
Five seconds later the Captain's, First Officer's, and standby airspeed indicators rolled back to 60kts. The auto pilot and auto throttles disengaged. The Master Warning and Master Caution flashed, and the sounds of chirps and clicks letting us know these things were happening.
"Jerry Staab, the Capt. hand flew the plane on the shortest vector out of the rain. The airspeed indicators briefly came back but failed again. The failure lasted for THREE minutes. We flew the recommended 83%N1 power setting. When the airspeed indicators came back we were within 5 knots of our desired speed. Everything returned to normal except for the computer logic controlling the plane. (We were in alternate law for the rest of the flight.)
"We had good conditions for the failure; daylight, we were rested, relatively small area, and light turbulence. I think it could have been much worse. Jerry did a great job flying and staying cool. We did our procedures called dispatch and maintenance on the SAT COM and landed in Narita. That's it."
Northwest and Delta should inform the public that have replaced all Thales pitot speed sensors on all their A319, A320, A330, and A340 planes.
Notez bien que le Copilote , interviewé , évoque le fait que , en vol de nuit , fatigué , en turbulences , l’incident aurait pu être bien plus ( much more) grave !
CQFD