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AF447

Old 5th Jun 2009, 20:09
  #181 (permalink)  
 
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Is there a possibility, that the actual ZFW of the plane was substantially higher than calculated and entered in the FMC?
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Old 5th Jun 2009, 20:10
  #182 (permalink)  
 
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RE: WX Radar

I'm an old radar guy (not a pilot) and I'd like to offer the following.
Display Color Rainfall Density
RED 12mm/hr or greater (about 1/2 inch/hr)
YELLOW 4 - 12mm/hr
GREEN 1 -4mm/hr

The Doppler mode detects the mezzo-cyclones within a cell by measuring the horizontal motion of the raindrops. The RDR-4A used a dual pulse signal for doppler. It measured the change in spacing (time) between the transmitted pulse pair and its reflected pulse pair. It could detect anything greater than 6 meters per second and display that in MAGENTA.
For those of you who like to play with GAIN control (if you have one) should know that when you change gain your display colors are no longer CALIBRATED!!
Regarding AF447, if they did encounter ice, it's possible that ice may have accumulated on the radome, and potentially may have attenuated the radar signal. That could explain how the radar could become inaffective without an actual failure.
I flew with a DC-10 Captain some years ago who asked me why the radar quit just when he needed it the most. He had attempted to land at IAH and hit what he said was a solid wall of water. He told me that the radar displayed a narrow band of noise and nothing beyond. Well, a solid wall of water would certainly attenuate the radar's signal, hence no returns beyond.
Hope this helps a little.
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Old 5th Jun 2009, 20:17
  #183 (permalink)  
 
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To Starbear:

I would not hesitate to use speedbrakes in order to slow down from an "speed going in the zipper" condition. I stand to be corrected.
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Old 5th Jun 2009, 20:21
  #184 (permalink)  
 
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I´m an old radar guy as well

Being meanwhile retired after more then 35 years of service in an european ATC / UAC centre I have a question to the professionals posting & reading here : a/c sending problem reports like AF about electric things, pressure loss etc., do they not transmit same time coordinates lat/lon where things happen ? kind rgds, golfyankee
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Old 5th Jun 2009, 20:21
  #185 (permalink)  
 
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Ladies and Gentlemen,

According to some of the data that Air France maintenance received in the last 4 minutes of AF447, I believe that the first ECAM that the crew may have received was NAV ADR Disagree. This would have been a level 2 warning. This particular ECAM warning would have had serious implications and would have been followed by a series of warnings.

When you have a NAV ADR Disagree, the ECAM action will ask you to check your airspeed and if it is erroneous then you should proceed with the ADR Check Procedure. But more ECAM warnings will now follow.

The next ECAM should have been Flt CTRL Alternate Law (Prot Lost). This would have been picked up by one of the Prims and the result of this now is that the Autopilot will disconnect. With the disconnection of the autopilot the priority of the ECAM will place Auto Flight AP OFF at the top and in red. Note that that the ACARS sent back Rudder Travel Limiter Fault, well this is one of the inop systems in the Alternate Law which follows the ADR Disagree.

If this was the sequence that the ECAM presented itself to the crew, the situation would have been very confusing and even for the most experienced of Airbus Pilots it would be difficult to handle correctly.

Assuming that this was the sequence, the Auto pilot was now disconnected and not recoverable at this time. Applying the ECAM action correctly is critical. After the auto pilot is cleared from the ECAM the next would be the NAV ADR disagree. But you would now have to check to see which ADR or ADRS are causing the problem. Remember the ECAM does not tell you Unreliable Airspeed so if there is a discrepancy then the next thing to apply is the memory item for unreliable airspeed.

AP/FD OFF
Auto Thr OFF

They were in level flight so the rest of the items need not be mentioned. Next would be to check what the GPS is showing as speed and altitude. Now you can proceed with the ADR Check procedure.

With the Alternate Law situation which resulted in the NAV ADR Disagree, Alternate Law is latched and resetting the Prims will not change the aircraft back to Normal Law.

Did ice cause this? Let us look at a case which only happend a year ago to QR somewhere in Asia. Airbus was well aware of a phenomenon of supercooled water droplets which exists in CBs and in areas around the CBs. These supercooled water droplets can adhere to an airframe/engine even at temperatures below -40C. QR suffered a dual engine flameout as a result of this. And Airbus has now mapped out particular areas of the world where this phenomenon is known to occur. It lies along the ITCZ, Sri Lanka and near the Philipines. Heavy icing is known to exist in these parts of the world.

The action of the crew with the erroneous airspeed is the most important thing that everyone needs to know. In the memory items the auto thrust would have been OFF and now the real speed of the aircraft would increase and be well beyond the turbulence penetration speed of .80. The MMO is .86 and the MD would be at .90. Did the crew set the correct N1 on the engines as indicated in the unreliable airspeed tables? Did they retard the thrust and stall when they were in Alternate Law? There are too many variables here to pinpoint exactly what occurred. But I do believe that Airbus is now on the right track.
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Old 5th Jun 2009, 20:28
  #186 (permalink)  
 
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@GY

Lat/Lon data is generally not part of automated maintenance type messages, although the equipment can be programmed to append such data for dispatch purposes.

@Safety Concerns

Yes of course, new information is always welcome.

My request was aimed at eliminating the mass media's spewing of speculative garbage that was getting copied and pasted into our discussion.
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Old 5th Jun 2009, 20:31
  #187 (permalink)  
 
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To be found, or not to be found . . .

If not located in the next few weeks, finding the aircraft -- and the FDR and CVR -- will become a function of the will to do so (time, money, political input). The required technology and equipment exist and will be made available as long as the will exists to continue location and recovery efforts.
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Old 5th Jun 2009, 20:34
  #188 (permalink)  
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"INTOL/M082F350 UN873 SALPU/M082F370 UN873..."

Decoded, this means the flight intended to cross INTOL at Mach 0.82 and FL350, proceed along the UN873 airway and cross SALPU at Mach 0.82 and FL370. In other words, the canned flight plan called for a cruise climb from FL350 to FL370 between INTOL and SALPU and before disappearing.

Do we know if this cruise-climb was performed? If it was, would not the A330 have been even more deeply embedded into its "coffin corner?"
Nope, it means that after SALPU the flight is requesting a level change to FL370. Any change in level would be issued by ATC (whether a cruise climb or not) and would be dependent on other traffic and whether the pilot actually wanted a level change or not from his current level. The pilot wouldn't change level on his own initiative, unless complying with Loss of Communications procedures. In that case there are criteria for making the level change, and based on the filed FPL, it would not occur until after passing SALPU.
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Old 5th Jun 2009, 20:56
  #189 (permalink)  
 
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Alert TD on all Airbusses

It looks like, all pitot tubes on 320,330, 340
have to be replaced to another type
within 2 weeks.
connector is offline  
Old 5th Jun 2009, 20:59
  #190 (permalink)  
 
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Connector,
Alert TD on all Airbusses
It looks like, all pitot tubes on 320,330, 340
have to be replaced to another type
within 2 weeks.
Any reliable source (EASA / FAA / Airbus) for such a stringent action ?
llagonne66 is offline  
Old 5th Jun 2009, 21:02
  #191 (permalink)  
 
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Many people are using the ACARs data at ‘face value’ without considering what precisely is indicated. What does the pitot readout mean; e.g. is it an indication of pressure mismatch or a failure of the anti icing heater system, etc?
Depending on what and how a problem is detected by the fault system, the specific problem could range from an electrical failure (heater), a leak, or icing (data mismatch). Speculation might then be based on the better understanding of these aspects .

I am familiar with icing problems with TAT probes. Some probe types suffered from ice ingestion in similar met conditions to those reported. These probes did not fail, but because the airflow path was restricted by micro ice crystals the probe erroneously measured ‘0’ deg C – the temperature of the static ice, opposed to the dynamic airflow flow. Presumably, without knowledge of a comparison or memory value, this would not trigger a ACARs fault.
Thus in these rare conditions, TAT can change value significantly (-50 to 0) without change in aircraft condition; whereas ‘Classic’ pitot icing normally traps pressure and a problem is not identified until there is a change in the aircraft state – speed / altitude.

Aircraft with multiple TAT probes could encounter either single or multiple problems. Systems using TAT information (e.g. ADC) might be able to identify a difference in TAT values and thus ‘flag’ a fault, but often (with single systems) the erroneous TAT is used by the aircraft systems.
It may be of interest to understand where and how TAT is used in the A330 and, together with the pitot system, how faults are generated. e.g. does the ADC use TAT for Mach / Alt correction? Would a mismatch of erroneous TAT cause the ADC’s to ‘miscompare’ – the resulting fault leading to the reported FGC, rudder limiting, and control ‘faults’?

The conditions for TAT probe icing can be encountered at considerable distances from a Cb; they are not easily identifiable with WXR, simultaneous aircraft icing is unlikely. The very fine ice particles (occasionally mixed with water) can be found in and below the anvil of large storms, hence a deviation of 20-30nm from the Cb core might not be sufficient to minimise the icing risks.
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Old 5th Jun 2009, 21:10
  #192 (permalink)  
 
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Route Planning

Someone mentioned earlier in the thread about AFR dispatch route planning and Briefing material given to crews. I am curious to learn about say an FAA co-authority dispatch method on this type of route vs. say the EU driven (or lack thereof) approach. Under the FAA system is the route more likely to be 'modified' due to FCST ENRTE WX? I believe that the EU system is most likely 'company route' driven with little or no consideration as to potential SVR ENRTE WX.
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Old 5th Jun 2009, 21:15
  #193 (permalink)  
 
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PITOT

LLAGONNE66

Its on Yahoo-news.
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Old 5th Jun 2009, 21:21
  #194 (permalink)  
 
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@ vapilot2004
but wouldn´t it be worth an idea to think about ? rgds, gy
In this case, yessir, last known Lat/Lon info would have been very helpful for SAR.
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Old 5th Jun 2009, 21:25
  #195 (permalink)  
 
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AF 447 SAR Effort

Gentlemen,
In view of the somewhat contradicting information released so far in the media, I think that it would not be a bad idea to provide a brief re-cap regarding the AF447 SAR effort. Most of the information was collected from Brazilian AF and Brazilian Navy press releases, with some B/C work with local contacts

June 1
a) At 0230LT/01062009 a C-130H staging through SBRF and an Embraer P-95 maritime patrol acft based at SBSV were enlisted to perform the initial SAR effort;
b) At 1908LT/01062009, the following additional SAR assets were called-up:
- 01 x Sikorsky UH-60L Black Hawk to SBNT;
- 01 x SC-95C (SAR version of the EMB-110P2) to SBNT;
- 01 x CASA C-295M SAR-configured acft to SBNT;
- 01 x Eurocopter AS332M SAR-configured helicopter to SBNT;
- 01 x C-130E to SBNT with SAR rescue teams;
- 01 x C-130H to SBFN, backtracking along AF447s flight path from GCLP to SBFN;
c) At 1930LT/01062009 Embraer R-99B 6751 SIGINT/ELINT acft was enlisted to aid in the AF447 SAR effort;
d) On 01062009 During the day the Brazilian Navy deployed the ocean patrol vessel NPa Grajau, the corvette Cv Caboclo and the frigate Constituição to assist in the search effort. The last mentioned ship was deployed with a Super Lynx ASu/ASW helicopter configured for SAR work.

June 2
a) At 0029LT/02062009 The Brazilian AF stated that the crew of a TAM flight inbound to Brazil spotted "luminous points" on the ocean's surface within the boundaries of the Dakar ACC
b) At 0100LT/02062009 Brazilian AF R-99B 6751's synthetic aperture radar plotted metallic and non-metallic debris floating on the ocean surface roughly 650km NE of SBFN;
c) At 0649LT/02062009 Brazilian AF C-130H 2466 and C-130H 2474 made visual contact with debris plotted by R-99B 6751's SAR. The debris fields were approximately 59km apart and roughly south of AF447's flight path. The debris fields contained an aircraft passenger seat, an orange float or buoy, a drum or cylinder, several small unidentified white-colored items and oil/jet fuel slicks.
d) At 1220LT/02062009 Brazilian AF SAR acft sighted small white parts and wiring roughly 700 km NE of SBFN, as well as patches of oil along a 5-km long strip.
d) On 02062009 In the morning, of the five merchant vessels called to assist in the SAR effort (MV Lexa Maersk, MV Jo Cedar, MV UAL MTEXAS, MV Douce France and Stolt Inspiration) two had arrived at the general area where the two initial debris fields were spotted
e) On 02062009 The Brazilian Navy deployed a second frigate - the Bosisio - as well as a tanker ship.
f) At 2100LT/02062009 A KC-130H 2462 departed SBGL to SBNT to join the SAR effort.
g) At 2140LT/02062009 A C-130H departed SBAF to SBNT to join the SAR effort.
h) On 02062009 A USN P-3C Orion detached to Costa Rica was deployed to SBNT to join the SAR effort
i) On 02062009 A AdlA Dassault Falcon 50MER was deployed, from Dakar to SBNT to join the search effort.
j) On 02062009 Brazilian AF R-99B 6751 ELINT/SIGINT acft and an Embraer P-95C 7100 maritime patrol aircraft were deployed to SBFN

June 3
a) At 0340LT/03062009 Brazilian AF R-99B 6751 ELINT/SIGINT acft plotted four small debris fields approximately 90 km South of the other debris fields located the previous day. One of these debris fields, approximately 5-km in diameter, contained several unidentifiable objects. Other items that were plotted included a 7-meter long object, 10 smaller metallic objects and a 20-km long oil slick;
b) As of sunrise/03062009 Three Brazilian AF C-130Hs, one USN P-3C and an AdlA Dassault Falcon MER departed SBNT to perform search patterns over and adjacent to the debris fields plotted over the preceding 36-hours, as well as continuing with planned search patterns;
c) Morning/03062009 Brazilian Navy patrol ship NPa Grajau arrived at the search area, initiating a “toothcomb” search pattern over a 120-km area centered on the 5-km debris field plotted earlier by R-99B 6751.
d) Afternoon/03062009 Brazilian Navy corvette Cv Caboclo arrived at the search area
e) Evening/03062009 The six aircraft directly engaged in SAR tasks had covered 176.984 sq km
f) Late Afternoon/03062009 The three MVs engaged in SAR work departed the search area.

June 4
a) Early morning/04062009 Brazilian AF R-99B plotted new debris fields SE of the St.Paul & St. Peter Rocks
b) As of sunrise/04062009 Three Brazilian AF C-130Hs, one USN P-3C and an AdlA Dassault Falcon MER departed SBNT to perform search patterns over and adjacent to the debris fields plotted over the preceding 36-hours, as well as continuing with planned search patterns;
c) As of sunrise/04062009 Brazilian AF UH-60L Black Hawk executed a search pattern 110-km NE of SBFN
d) 1140LT/04062009 A Brazilian AF C-130H sighted a new debris field some 550 km from SBFN, vectoring Brazilian Navy frigate Constituição to the area. That ship’s Super Lynx was launched to retrieve items from that debris field, which included a wood pallet bed and buoys. It was ascertained that neither were linked to AF447.
e) Afternoon/04062009 Brazilian Navy Frigate Constituição sighted a large oil slick some 80km from the site it had earlier been vectored to, the ship collecting oil samples for later analysis.
f) Evening/03062009 Aircraft directly engaged in SAR tasks had covered 185.349 sq km

June 5
a) Morning/05062009 An AdlA Breguet Atlantic joined the SAR effort
b) Morning/05062009 Degenerating weather conditions (thunder showers, sea state 3 and visibility of 4km ) were expected to hinder scheduled aircraft search missions

Cheers
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Old 5th Jun 2009, 21:29
  #196 (permalink)  
 
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TV CNN press reporting BEA to hold 2 hour briefing tomorrow (Saturday)
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Old 5th Jun 2009, 21:48
  #197 (permalink)  
 
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Nope it's supposed to keep level and speed

[quote]
Quote:
"INTOL/M082F350 UN873 SALPU/M082F370 UN873..."

Decoded, this means the flight intended to cross INTOL at Mach 0.82 and FL350, proceed along the UN873 airway and cross SALPU at Mach 0.82 and FL370. In other words, the canned flight plan called for a cruise climb from FL350 to FL370 between INTOL and SALPU and before disappearing.

Do we know if this cruise-climb was performed? If it was, would not the A330 have been even more deeply embedded into its "coffin corner?"
Nope, it means that after SALPU the flight is requesting a level change to FL370. Any change in level would be issued by ATC (whether a cruise climb or not) and would be dependent on other traffic and whether the pilot actually wanted a level change or not from his current level. The pilot wouldn't change level on his own initiative, unless complying with Loss of Communications procedures. In that case there are criteria for making the level change, and based on the filed FPL, it would not occur until after passing SALPU.[/quote]
(my underlining)

PPRuNe Radar:
The pilot shall proceed in accordance with the last received and acknowledged oceanic
clearance, including level and speed, to the last specified oceanic route point
, normally
landfall, then continue on the filed flight plan route. The pilot shall maintain the last assigned
oceanic level and speed to landfall and, after passing the last specified oceanic route point;
the pilot shall conform with the relevant State procedures/regulations.
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Old 5th Jun 2009, 21:48
  #198 (permalink)  
 
Join Date: Nov 2000
Location: Montgomery, NY, USA
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Alert TD on all Airbusses
It looks like, all pitot tubes on 320,330, 340
have to be replaced to another type
within 2 weeks.
From a manufacturing point of view, is this possible? Are these common interchangable parts? Are they common stock items available in such quantities?
patrickal is offline  
Old 5th Jun 2009, 21:56
  #199 (permalink)  
 
Join Date: Oct 2006
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Question Backup Speed Scale

My outfit has retrofitted all 330/340 machines with Backup Speed Scale function. In a nutshell, if unsure which ADR(s) is/are faulty, switch them all off and- voila! Keep the "speed" out of red by using power and attitude (note: two red bands, one above, one below the speed reference line on speed tape). Altitude displayed is derived from GPS.

I'm just curious whether this particular MSN had the same retrofit done or not.
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Old 5th Jun 2009, 22:17
  #200 (permalink)  
 
Join Date: Jun 2008
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PITOT

Patrickal

Its no big deal to replace a couple of pitot/tubes
on an AiRBUS.
Lets say, 4-5 hours, including test.
But like you say, are there spares?
In situations like this, the manufactor is not able,
to follow the demand.
Maybe, they are not even finished, to design the probe.
But they have "talked" to Airbus about it.
I like EASA, but its like a "postoffice",
Things take time.
connector is offline  

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