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-   -   Air France rejected T/O in Lagos (https://www.pprune.org/rumours-news/403563-air-france-rejected-t-o-lagos.html)

Bernoulli 27th Jan 2010 21:28

Previous poster just beat me to it! Here's a link to the RTO tests on the A340. It's got to be pretty serious to consider a stop at high speeds. The AF chap would have been convinced his aeroplane wasn't going to fly so did what he thought best in the couple of seconds available to him. As for taxying far afterwards..... well.....:ooh:

YouTube - Airbus A340-600 Rejected Take-Off test (subtitles)

(sorry, don't know how to do that embedded video thing)

Bernoulli

hetfield 27th Jan 2010 21:40

Oh my God:O

Please oh Lord, let it be a fake.....

sitigeltfel 27th Jan 2010 21:48


Originally Posted by Bernoulli (Post 5474707)

(sorry, don't know how to do that embedded video thing)

Bernoulli.............check your PMs.

Locked door 27th Jan 2010 22:00

'Tis not a fake. The problem with the a340 test was the fusible plugs failing to melt at the correct temperature, leading to tyre overpressure explosions that put flammible material in contact with the brakes. In the 777 test you see the tyres deflate before the five minutes is up, but this is perfectly allowable. The a340 test was repeated with different plugs and all was well.

It's worth bearing in mind that your fusible plugs may perform just as badly when you reject, whatever type you're in. Always a good idea to get the fire services to your location pronto, even if all seems well initially!

LD

atakacs 27th Jan 2010 22:12


In its maidem operations on the new route, the airline said it would now combine the Paris-Lagos flight, with the direct Paris-Port Harcourt flight previously operated with an Airbus 319 aircraft.
Sounds like a pretty long route for a 319...

beaver34 27th Jan 2010 23:55

it's an A319 with additional center tanks

CONF iture 28th Jan 2010 02:39

Thanks for your comments.

On the Airbus side, information is minimal :

If tire damage is suspected after RTO, inspection of the tires is required before taxi. (some restrictions apply depending the number of damaged tires)
IMO Airbus should provide something more substantial on the subject. A chapter in the Abnormal Operation of the FCTM would be the right place.

Other questions :
  • What kind of equipment use the firefighters to cool down the brakes ? Are they simple fan blowers ? What is the procedure for the firefighters after a RTO ?
  • Also, I’ve been told that some RTO can even require a landing gear replacement depending on the level of heat accumulated in the landing gear body … Any comment ?

DA-10mm 28th Jan 2010 06:00

Saint-Ex:

...or leaving their FIR...

hetfield 28th Jan 2010 07:16


  • What kind of equipment use the firefighters to cool down the brakes ? Are they simple fan blowers ? What is the procedure for the firefighters after a RTO ?
  • Also, I’ve been told that some RTO can even require a landing gear replacement depending on the level of heat accumulated in the landing gear body … Any comment ?

a) AFAIK they use water/foam. Fan blowers would increase the risk of a brake fire.
b) Yes, if the boogies get too much heat they must be replaced

Cheers

wings folded 28th Jan 2010 11:53


b) Yes, if the boogies get too much heat they must be replaced
The only way my boogies get too much heat is when I stick a lit match up my nostril.

I rarely do it nowadays because it is not very comfortable.

Huck 28th Jan 2010 12:10


Close the loop. If you don't, one day, something will bite you.
I prefer:

"Live another day. Check your FMA...."

moonburn 28th Jan 2010 12:13

What kind of equipment use the firefighters to cool down the brakes ? Are they simple fan blowers ? What is the procedure for the firefighters after a RTO ?

Air conditioning carts are ideal, however I have used air start carts many times and although the airflow is warm it is still very effective in reducing brake temperatures to safe levels, you will usually have to 'do it yourself' as most ground staff will not go anywhere near smoking wheels. If fire is already apparent the only really safe option is dry powder extinguishers,although Co2 can be bounced off the tarmac and onto the fire. Co2 or water directed straight onto the gear will nearly always cause catastrophic thermal shock and explosions containing shrapnell as well as rubber. Oh yeh, and ONLY approach from fwd or aft or you could recieve a facefull of wheel !
Safe flying.

Nil defects 28th Jan 2010 12:52

Quote: "Lagos was a short stop to board some pax. The crew failed to arm AT before departure. On takeoff, pushing TOGA didn't engage AT (because, it wasn't armed)."

So why were the autothrottle arm switches off? There is no reason to turn them off and particularly as the aircraft was on a transit stop anyway.

But even on a normal turnaround or long nightstop there is no reason to turn the auto throttle arm switches off. There is no Boeing procedure that calls for them to ever be selected off on the 777 (except in a non normal or engine failure type event)

:ugh:

Dont Hang Up 28th Jan 2010 12:55

If jeff64's figures of 161kt and 0.48g deceleration are reliable (and assuming 300 000 ToW) then at the onset of deceleration the braking force would be generating 117 Megawatts.

The aircraft would have stopped in just under 18 seconds covering around 730 metres (lucky to have that much left at Vr).

The total heat generated would be around one billion joules - sufficient to heat two and a half tonnes of cold water to boiling point.

Tea anyone?

jeff64 28th Jan 2010 13:24

Nil defects : I don't know why. Don't know the AF 777 procedures, but on the 744, the after landing flow (air france procedure) requires the AT switch to be turned OFF. Maybe it is the same on the 777.

Dont Hang Up : The figures come directly from a note written by the AF 777 chief pilot to the AF 777 drivers. The original image is below (in french)
http://img215.imageshack.us/img215/3712/stop777001.jpg
http://img687.imageshack.us/img687/9377/stop777002.jpg

captplaystation 28th Jan 2010 13:49

Well, at least it will give the Air France "Safety Panel", that flightglobal.com say is starting its interviews next week, something topical to discuss, rather than same old same old :D

IFR OnTop 28th Jan 2010 15:04

RTO, LOS
 
Being not a 777 jock I do fly the 73 NG's. So as it's of the same family I guess there are some similarities.
1) The " Before t/o check list" does it specify "Autothrottle....Arm"
2) what is the PF doing pressing buttons on the takeoff roll when his head should be "outside"?
3) What is the PM doing, Im sure, "outside" when he is suppose to be monitoring PFD's, ND's, Eng Inst, etc?
Anyway mine is not to criticise the pilots but it seems that when there is a slight deviation from the norm human instict takes over and survival mode kicks in.
If CRM/SOP's was followed it would be a simple case of back to basics and doing a bit of manual flying.
We learn everyday.

despegue 28th Jan 2010 17:18

maybe your checklist on the B737 says "A/T Arm" but mine certainly doesn't and it is sometimes forgotten. Not a big deal, you don't NEED an A/T anyway...

fdr 28th Jan 2010 21:16

B777 Atr
 
The B777 Auto throttle, ATR is not like the B737, B744 or B757/767 system.

It is a true full time system, and there is only NNCL procedures to disarm the ATR, unless a Flight operations department has decided to apply their corporate wisdom to change the manufacturer's procedure. This can occur from either a operator perceived deficiency in the manufacturers procedures, to standardise with other types in the operators fleet, etc... Where the procedure deviation may vary from the AFM, then a No Technical Objection is required from the manufacturer.

There is no normal condition where the ATR is better served by being turned off, including single engine operations (although if you have no TAC, no PFC's and degraded hydraulics and single engine, it is easier to fly manually without the ATR.... ). On a manual landing at 25'RA the ATR retards the thrust to idle, unless the aircraft mode is FLCH or TOGA.... The pilot is not restricted in overriding the ATR manually at any time, and once the override pressure is released, the throttles revert to the commanded thrust level. it is infrequent that this occurs, even in modest windshears, IMHO (~8,000 PIC on type).

ref: FCOM 4.20.8, FCTM,

This is in stark contrast to the B737/747/744/757/767 system design and performance.

AF did have a mishap related to manual flight with an inadvertent ATR re engagement on a B744 landing at Tahiti, which ended in tears and photo opportunities, which would certainly tend to make people cautious about the ATR arming switches of a B744, but the B777 is not in so many ways (good and bad...) a B744.

This event should be a wake up call for AF, it is an opportunity to learn from an accident without having suffered same, as this very nearly was a catastrophic event. maturity of their flight operations department will be evident in their response, either shooting the messenger, or working out why their system of training, procedures, and practices failed miserably on the day, and by the benevolent smile of lady luck avoided a major mishap, from a minor procedural oversight.

The decision to continue a takeoff in manual thrust when the ATR does not engage in TOGA mode is one that I have misgivings on, as it indicates a technical or operational defect exists in a time critical phase of flight. The FCTM procedure does not call or suggest fault finding, just manually applying the requisite thrust level. fault finding and mode changing on the fly is a potentially hazardous proposition, as either an error of analysis, switching or other can occur and little or no crosschecking will be conducted. This is anathema to 2 pilot operation SOP's. The subsequent defect identified by the pilot of a flight control restriction at the point of initiating the rotate, is apparently not cognitively linked to the non standard procedure of engaging the ATR (accidentally engaging the AP). The mode changes are not identified by the crew apparently on the roll during this event at all, indicating some limitations of monitoring of crews in a high workload environment. This is not a criticism of the crew per se, it is an observation of the limitations of the human to cognitively multi channel in a dynamic environment. The oversight of the ATR switch in the preflight check, where it is listed in the POM, Ch5.3 needs also to be assessed in the light of duty time/fatigue/etc before lining up the messenger against a suitably pockmarked wall.

This event should serve as a warning to any organisation that is complacent in their operational safety record, procedures and CRM principles, to the point of hubris.

Flight Detent 29th Jan 2010 01:31

just my 2 cents worth....

I am 100% behind the comments of "411A" here, why oh why have we gone this way, it's proving inept time and time again! (even the original idea for the change has been proven rubbish!).

Yeah...I know...all the pilots will come back in a gigantic wave telling me they don't need a professional Flight Engineer, he's not needed, we can do it all ourselves.

BUT...it's being demonstrated time and time again that 'when everything's fine, everything's fine", but when you REALLY need instant technical expertise/another set of eyes, right there in the flight deck, the PFE is being missed sorely!

This is simply another example of that, one that seriously could have ended very, very badly!

I normally say "Cheers" at this point, but I don't think it's appropriate in this environment!

FD:yuk:


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