The answer to all our secrets
 

Went to Birmingham on Saturday PM and watched this Monarch A320 take off and noticed that the undercarriage was staying down for an unusually long time. Then heard the pilot inform the tower not to worry as they were leaving it down on purpose and off they went with it still down.

Anyone suggest a reason?

I have heard of this done before when the guys took off with high brake temps. If you pull the gear up then the temp falls much slower. I whon't comment on whether they should have taken off with high temps in the first place regarding perf and sop's. I have sat agast once though with my training Captain listening with interest when an F/O explained how they took off with 2 temps at 350 and just 'left the gear down to cool them a bit'. Find this hard to believe with Monarch though, very high standard of SOP's etc. They may have had an ecam indication, windshear warning etc wher they thought better just to climb up a bit before sorting things. When you raise the gear the doors open and in fact cause an increase in drag, if you have something happening windshear for instance then that's the last thing you want to do so you leave it be. One would have thought though they would have given some indication to ATC, but when you are climbing out of Birmingham and maybe you have a slight problem your RT could be effected.

Nothing too unusual and I've seen it lots of times. I told an Air France Airbus he had his gear down as he climbed away. "Affirm; we use it for take-off" was the response!

I can rem some years ago a 747 Classic getting a call from the Tower after take-off, querying why it's U/C was left down? ..... just cooling the brakes came the reply ..... :)

Can I ask why the brakes would get hot on take off?

Most likely a brake problem (usally a tachometer) that means that the brake has been disconnected. The brakes are applied automatically during the retraction sequence to stop them rotating, if the brake is disconnected then you have to leave the gear down for 2 minutes after take-off to allow it to stop spinning. Quite why it's considered such a problem to have them rotating in the wheel well I don't know. Take-off and landing performance are both reduced via a table with one brake inop, and obviously if you have an engine failure you retract it anyway.

you leave the gear down when the brake is deactivated till the wheel stops (2 mins) as the wheel acts as a jyro and will put wear on the undercarriage because of the strain of moving the wheel through 90 degreases and slows the retraction on that side by up to 90secs (a300)

when landing you apply manual braking and the temps go up. If for some reason (usualy a bit heavy footed on them) the brake temps are high you need to cool them. Some aircraft have brake cooling fans that you switch on to help. But if you havent got these and you are on a short turn around or the pilot applies to much braking in the taxi to takeoff then you have high temps again. Most likely that the pilot flying could have been under line training and a bit to heavy on the feet but as you have read there could be a thousand reasons

I was the FO. Captain called 'GO' just before 100kts when we got a BRAKES HOT Amber ECAM warning on one brake - only 300ish degrees. We decided to leave the gear down to cool it off and the Captain made a great call to the tower so everyone knew what was going on. Cooled it down, got them up, and off to wherever we were going. Probably a quick turnaround and the long taxi down to 15 put some heat into the brakes.

Fatboy slim

I have it on video, if you want a small AVI of yourself let me know.

The answer to all our secrets
 

When Commercial style Aircraft steer during taxiing, what parts of the actual Aircraft are used to carry it out?
I always notice the actual nosewheel turning, but was wondering whether using left or right engine thrust and the rudder assists.
Also on a recent flight I was on (A320) I noticed the Aileron being raised on a wing (depending on the direction turned).

Nosewheel normally via a steering wheel in the cockpit.

Use of aileron while turning on the ground is unusual - mind you, an Airbus............................:ugh:

In A320 aileron movement will be when flight deck are doing the flight control checks. First PF then PNF (or Capt then FO depending on SOPs) does them so you will see them move twice.

Normally most of the steering is done by the nosewheel. Sometimes differential power can be used on tight turns but it can put more strain on the main landing gear.

what about differential braking like in a light a/c? Is this done in jets when taxiing around tight corners?

With the larger aircraft unless it is tight the nose wheel steering is anough for turning.

Where large aircraft need to turn on the runway to backtrack for a turn off yes the engine power does need to be used.

Light twins do not normally have sperate steering it is done through the nose wheel and braking and the engine help in the turn.

Aircraft from the commuter size seem to be the first aircraft to have a steering wheel or tiller (A Twin Otter has a tiller this is like a column change gear stick in a car up to turn right and down to turn left).

Sometimes controllers put pressure on pilots to do a tight 180 degree turn on the runway which does put a strain on the near undercarriage leg, an Aurigny Air Services ATR went into engineering with in the last week with a cracked undercarriage some tight turns may have caused or not helped this.

Our runway is 46 metres wide the turning circle i understand for a Boeing 757 is 45 metres so you have not got a lot of room either side, aircraft have gone farming before now by turning on the runway and going over the edge.

Not only the pilot being red faced but the controller could take some of the blame by better use of the taxiways or dumbell turning circles at the end of some runways thats my oppinion any way.

Try a Tiger Moth for fun.

No brakes, no steering other than power and rudder or a handler on each wing-tip.

Downhill and downwind, you need to be very careful.

contrails
 

HELLO>>>FRIENDS¬!!!

What exactly are contrails?
What makes them occure?
Has ist anything to do with polution

all you ever wanted to know about Contrails ....

try this Google ....

http://www.google.ie/search?hl=en&q=...trails%3F&meta=

Contrails..... a "shorthand" for
Condensation Trails. The Hot Gases exiting a Jet Engine leave a "Vapour Trail" across the sky. It is merely the hot air [exhaust] meeting the cold air [atmosphere], and being visible. At different altitudes, the Con/Vapour trails are NOT visible due to atmospheric conditions...[temperature/pressure gradient..etc]. Converely, sometimes, due to the same "atmospheric conditions".....Con/vapour trails seem to last for eveeer ........:ok:
hope this helps
watp,iktch
thanx hobie

your very welcome .... :)

In the 747 There is one tiller per side for steering. Maximum deflection of the nose wheel is 70° either side of straight ahead. When 20° is reached, body gear steering is automatically engaged. With the rudder pedals, a maximum of 7° deflection can be reached.

It is a very strange feeling when looking out of the cockpit doing a tight turn, almost as though the aircraft is reversing or sliding sideways. (if that makes sense)

Hot brakes
 

Lots of rubbish above!

A320 carbon brakes noticably heat up virtually any time they are applied, if he was on a quick turnaround there may have been some residual heat left in them from previous landing and taxy in, although use of the brake fans should have cooled them. With a long taxy out you would need the fans on again.

There is a potential for dirt/crap and even debris to be thrown from the wheels on lift off which can go into the bay and rupture hydraulic lines or worse in the case where a tyre seperates so best to stop then spinning straight away, thats why they are braked, if you dont understand this say CONCORDE several times and you will!

There can be several reasons for leaving the gear down after take off, cooling has already been mentioned, or perhaps even a problem with the sequence, sometime if you think you have a problem that might be gear related and need a return you may not want to run the gear up in case you cant get it down again! Its not always a good idea to explain to ATC exactly what is going on because the reporter with the airband radio will write it up as an a dramatic emegency which isnt good for the companies reputation or image.

A/C on a quick turnround,brakes still hot as no brake fans are fitted,A/C takes off brakes still hot after taxi(but below take off limit),cool them down with airflow before putting them into the hole.

Its as simple as that!

Carbon brakes are meant to get hot as they work better when upto working temp .

Certainly is isn't there, for instance:

What are you, a professional pilot or the company's own version of Max Clifford? As pilots we are responsible for using all resources available to us to ensure the safety and security of our pax and crew, including talking to ATC about any non-standard/non-normal situations which may occur. You may even find them helpful from time to time.

I understand that 330 ECAM logic does have some differencies over 32x, (not rated on 330 do not know which), but on 320 HOT BRAKES is inhibited during takeoff for good reasons. Only comes up at liftoff to advise crew not to raise the gear as opposed to woefully suggest stopping with a brake problem.

Fatboy, can you advise what is the BRAKES HOT inhibit phase for 330, pls?

FD.
(the un-real)

Max Angle: The other reason that you might want the wheels to stop turning before you retract them is to avoid the stress on the landing gear caused by gyroscipic presession.

Start number 1 Cross bleed number 2 ????
 

Something I here at my local airport, any kind sole tell me what it means, something to do with engines starts me thinks.

Nick.

Probably a 737, but may be other types too. When the APU is not able to suply air to start the engine, a ground-air unit is plugged in. On the 737 it plugs in on the right of the fuselage centreline. It is used to start No 1 (the left) and then disconnected (safely, away from the running engine - which is at idle only). Pushback takes place and number 1 is 'run up' to a medium power setting to provide enough air to start number 2 using 'crossbleed air'.

Other types may start number 2 on stand due to the location of the air connection.

A search will produce more. Here is one.

Many thanks BOAC.

Nick.

P.S. just wondering why my post was moved.

To the correct thread?:)
Have you read the announcement and this thread?

Holding Patterns!
 

Hi all, just been observing a BMI Baby 737 in the hold at 'MIRSI' on my SBS-1. The pattern it creates is an absolute perfect race track shape pattern! I take it that it is auto pilot and instruments that maintain this shape and pattern during the hold? any feedback from aircrew would be appreciated!

Regards, Steve

Post #21 A330 "HOT BRAKE" inhibit is from 80kts to lift off and again on touchdown to 80kts according to my FCOM which is not amended and quite old.

Thrust reversers prior to touchdown
 

http://www.!!!!!!!!!!!!!!/search/photo.search?id=0348313
This is quite an old photo but i was amazed by this . Boeing and Airbus models can do this ? And why a pilot would do something like this ?

You can't do that on an Airbus. For the thrust reversers to deploy the ground squat switch needs to be depressed. In other words there needs to be weight on the wheels. You can go into the reverse position with the thrust levers but the thrust will remain at idle until the aircraft touches down.

i'm not sure about the Boeing but i would think they are the same.

Hope this helps. Maz

Modern Boeing no, and I assume Airbus no also. There are 'switches' that need to be made before reversers can normally be deployed, such as weight on wheels, radio altitude and others. Maybe there was no protection on this Russian model.

Problems of doing it would be that if you could not retract the buckets and needed power...................................

I've no doubt some old Trident puke:D will be along soon to tell you that they used to use reverse on number 2 engine (yawn:) ). It may be that the B727 used it as well - in both cases to expedite descent.

Just beaten to the post by Maz:ok:

Thanks a lot for your replies . I've searched for western airplanes but i did not find a similar photo . I've never experianced something like this as a passenger but i assume it must be quite scaring . But i still don't understand why a pilot would do something like this instead of raising the speadbrakes for example

I seem to remember the DC8 had this reverse in flight for decent and short landing

Thrust reversers on 737-3/4/500 will deploy below 10ft Rad Alt. Usually achieves a rather firm touchdown :eek:

Yes there is isn't there?:rolleyes:
Most a/c I know only brake the wheels when gear selected up. They will spin away quite happily until hydraulic fluid is ported through the landing gear selector valve to the brakes.
As has been mentioned, the A320 MEL allows for a u/s brake, and SOPs state that the gear is left down for 2 mins after t/o to allow the wheel to spin down. (Gyroscopic forces and all that malarky apparently).:ok:

Yes you can reverse any or all engines on the 72 anytime one desires, as long of course you are at idle power. Now I do not believe that there were any procurers on reversing in flight published by Boeing, at least I never saw any. Personally I never reversed the number 2 in-flight to expedite a descent. I did reverse all 3 engines during a sim ride once when we wasting time at the end of a recurrency ride.

Instructor placed us over the outer marker of 26L at Lax, 250 Kts IAS, 10,000 feet, clean and said "Land it, straight ahead, no turns." I did, it was not easy and in no way would I ever try it in real life, unless I had no other option. Was kind of fun.