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visualwith737
25th May 2008, 13:47
Last year in May I took a trip to Northern Cyprus (NC) flying Turkish Airlines out of Stansted, as part of NC political set up all flights in and out of NC must first touch down in Turkey before heading off to their destinations, the flight into NC was all OK, however the flight back was interesting ... We took off from Ercan and set down in Dalaman as part of the required Turkish leg of the journey before setting back off to Stansted, we dropped some people off and took some people on at Dalaman, I was a passenger on this flight by the way! ... the flight was quite quiet this day so I had a row of seats to myself so was engrossed in my book when I noticed few passengers were getting quite irate with the cabin crew and were 'ranting' in Turkish about the delay in taking off (not that I'd noticed being into my book) I looked out of the window and noticed all the aircraft around us had come and gone, at this point I started taking notice of the aircraft movements on the ground, all were tracking to the south of the airfield and taking off into wind towards the north this clarified by the windsock which I could clearly see ... after sometime the Captain came on and told us the delay was due to the aircraft being too heavy and we were waiting for a bowser to come and pump fuel off the aircraft!!!? ... we then had to land in Germany to take more fuel on thus delaying the flight even more .. the bowser duly turned up but never coupled up and never took any fuel off .... very quickly after this the cabin rushed round to get the aircraft reay for take off and we very quickly got pushed back and started tracking the the North of the airfield?? I thought maybe he was going to taxi down the runway turn into wind and take off to the North .... er NO! He turned at the North end of the runway and as turning give full throttle and we were off heading south with the wind!!??! again verified by the windsock as we passed it!

Believe me we used every single inch of runway and he dragged this aircraft kicking and screaming into the air taking off with a very low angle of attack over the water and he kept this attitude until way over water before he started to increase his climb rate ... Why???

My thought is that he knew he was heavy so took off towards the sea knowing that if he had to abort and it all went wrong the sea was a better option than the mountains to the North ... any thoughts??

PS we didn't land in Germany!

IRRenewal
25th May 2008, 14:40
Why???

T/O to the south is over the water, so no mountains to avoid.

They probably were waiting until the tailwind reduced to within limits (hence the sudden rush to get the cabin secure when it did happen) and they took off with a tailwind.

Often in these places you can take more weight into the air with a tailwind without mountains ahead than with a headwind with mountains ahead.

Perfectly normal procedure, and done by any airline that flies at Dalaman.

visualwith737
25th May 2008, 14:54
Thanks for the reply, I understand although the windsock was pretty active that day but suppose it was a calculated 'risk' being a PPL holder and just started on my ATPL still got some stuff to learn eh!

Mungo Man
26th May 2008, 09:45
taking off with a very low angle of attack This doesn't make any sense. Low angle of attack is achieved at high speed. Take off would normally be at a high angle of attack. Anyway, did you have an angle of attack readout in your seat?

nowing that if he had to abort and it all went wrong the sea was a better option than the mountains...

suppose it was a calculated 'risk'

Airline pilots just don't work like this. They would have consulted the performance charts and if the data says they could get airborne off that runway with a tailwind then that's what they did. I have requested a tailwind take off before when the only other option was to offload passengers and take off into wind on a runway which was more limiting due to obstacles in the climb out path.

100hours
26th May 2008, 12:11
Very interesting indeed. Also myself as a PPL low time never knew this ! Thanks for this interesting info !

visualwith737
26th May 2008, 14:47
Hi, thanks for the reply, what i meant was the angle of take off was very much less than usually experienced on commercial take offs, and no I didnt have an 'angle of attack' readout in my seat and being a PPL holder just starting out on my ATPL I'm looking for reasons and experience not sarcasm from the people I look up to.

TopBunk
26th May 2008, 16:13
vw737

Just a thought ..... when you don't have all the facts, don't dramatise your thoughts with rubbish (such as 'perceived' low angle of attack and dragging the aircraft off the ground...), rather just ask the pro's for possible explanations. You just might get a better response.

I have been in South America (I am a 747 Captain) and have been given an incorrect fuel (already loaded) for the available runway and had to offload x tonnes of fuel, wait for the temp to drop 10deg C, the wind to shift to the better runway, offload freight and econ pax bags before being able to take off.

We consider many variables in our deliberations including crew hours, which may be limiting additionally), much of which is unknown to the general public.

BusBoy
26th May 2008, 16:23
visual - what was being pointed out (rather unhelpfully) is that AoA is different to Pitch Attitude

Musket90
26th May 2008, 18:47
I remember when flying on a DC10-30 where flight time was expected around 10hrs 30mins to 11hrs. Captain announced that he was delaying departure for an hour or so until temp dropped sufficiently allowing more fuel upload therefore more chance of reaching destination non-stop. Temp at the time was +30c with light crosswind. The aircraft rotated very late! Reached destination Ok but had to sit on taxiway for at least 30mins until parking stand change was organised as allocated stand was blocked by broken down vehicle. I'm sure captain was not amused.

Put1992
27th May 2008, 16:24
AoA is different to Pitch Attitude

Could you expand on this please, just for some personal knowledge.

thanks

Put

pierrefridez
27th May 2008, 17:00
well, briefly said:
AoA: angle at which air hits wing
PA : angle of fuselage relative to horizon
AoA is determined by PA, climb angle (angle between flight path and horizon) and angle of incidence (angle at which wings are attached to fuselage).

Hope this helps

Mungo Man
27th May 2008, 21:48
Could you expand on this please, just for some personal knowledge.

Or think of it another way. When the Red Arrows are climbing vertically their pitch attitude is 90 degrees but the angle of attack (angle between front edge/rear edge of wing and the airflow) is very small because the wings are not producing much lift - they are climbing mostly on engine thrust.

Vw737 - I wasn't trying to be sarcastic, rather trying to show that your description was vague and imprecice. But I think I know what you mean and don't mean to be unhelpful otherwise I wouldn't be wasting my time writing. When you are deeper into your ATPLs you will be able to analyse this a lot better and hopefully it will make sense. Any other questions feel free to ask or pm me.

Put1992
27th May 2008, 21:50
pierre and mungoman, thanks, that makes sense :ok:

Deano777
28th May 2008, 15:08
The correct terminology for AoA is the angular difference between the wing chord line & the relative airflow (note - relative airflow).
Pitch angle is the angular difference between the level horizon and the aircraft's longitudinal axis.

pierrefridez
28th May 2008, 16:31
much more precise wording than mine... good one!

Mungo Man
29th May 2008, 13:19
indeed Deano, but I was assuming that someone who doesn't know what angle of attack is might also not understand 'chord'

visualwith737
30th May 2008, 08:01
MM - thanks for your reply I do appreciate all replies and yes your right my terminology was incorrect, I now understand! ATPL here I come!!

mutt
30th May 2008, 11:44
dragged this aircraft kicking and screaming Can anyone kindly give me an explanation of how an aircraft Kicks and screams?

Mutt

visualwith737
30th May 2008, 11:51
Yes I can ...