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Chris the Robot
23rd Jan 2016, 09:17
Having read Handling The Big Jets by D. P. Davies, it appears that pilots were encouraged to learn to hand-fly jet transports at altitude and to remain reasonably current in this particular skill.

I was recently speaking to an A330/A340 F/O and he said that hand-flying at altitude was virtually forbidden because the aircraft was very sensitive, particularly in pitch, in this scenario.

I'm aware that in order to maximise various aspects of performance, modern jet transports are not the most stable aircraft but apart from software, what has changed in the past 50 years which makes these aircraft so difficult to hand-fly at altitude? Following AF447, I'd have thought that training and currency in manual high-altitude flight would be necessary.

FlightDetent
23rd Jan 2016, 10:29
The friend was being somewhat simplistic to you. That's not one of the reasons, especially on the Airbus FBW. Today's aircraft are not more complicated to handfly compared to those 50 years ago.

The skills and proficiency missing to save AF447 from its fatal end were not those you could learn or master by flying without the autopilot in cruise.

There is, however, a recognized industry initiative to adress those missing bits, look for "high altitude upset and stall recovery training", or similar. The key obstacles before tangible benefits are obtained are:
- lack of a precise mathematical model for the simulators;
- cost of the training.

Johnny F@rt Pants
23rd Jan 2016, 19:43
what has changed in the past 50 years

Separation, RVSM nowadays that wasn't in existence back then.

wiggy
23rd Jan 2016, 22:54
As Flight Detent said modern types (well certainly the Boeings, even the heavies) can be hand flown OK at high level, nothing really has changed, the problem is a legal one that is down to what Johnny FP has said, i.e. Reduced Vertical Separation Minima (RVSM)...

With vertical separation at high level reduced to 1000' (it used to be 2000') there's less of a buffer to cope with the inevitable plus/minuses around your assigned altitude that you will get on occasions when hand flying at high level. As a result various authorities/companies ops manuals pretty much forbid handflying except in exceptional circumstances/emergencies at high level.

Wageslave
24th Jan 2016, 12:39
With the standards of handflying today you'd quickly have pax and cabin crew irate at he rough ride and if you persisted a very messy cabin too.
Sorry, but thats about the size of it. Pax comfort.
Smoothness in hand flying just isn't thought important or emphasised in training these days, it seems. Neither is smoothness of braking. Awareness of the ride you're giving your pax was all but non existent in the FOs I flew with - (major loco).

Fursty Ferret
26th Jan 2016, 13:29
As far as I know there is no restriction on hand-flying in RVSM airspace; the restrictions are down to the equipment on board, not whether it's used or not.

I occasionally fly the A320 up to cruise and for a short time afterward with flight directors off. It's a very different beast compared to low level flight and very sensitive in pitch. You'll find yourself flying to about an 1/8th of a degree to maintain level flight.

Midland 331
29th Jan 2016, 18:24
Circa 1986, I jump-seated on a DC9 from Teesside to London, and the captain (possibly Barney Concannon) hand-flew for most of the time. He was ex-RAF, and his skills were sharp, even in his sixth decade.

When asked by the FO "why", he replied that there wouldn't be that many chances to do it in the future. Wise words.

KBPsen
29th Jan 2016, 20:34
As far as I know there is no restriction on hand-flying in RVSM airspaceThen you don't know the RVSM requirements.
An automatic altitude hold system is required to be used unless you are climbing or descending.

despegue
30th Jan 2016, 01:42
You ARE allowed to fly manually in RVSM. The requirement regarding autopilot is just serviceability, NOT usage.

Fursty Ferret is thus correct. And who the hell can not keep within 50' as a Professional pilot?!?!

TopBunk
30th Jan 2016, 07:31
Pre-RVSM days I remember hand flying a B737-200 from Madrid to Gatwick as both autopilots were u/s.

Me and my oppo took turns for about 10 minutes at a time.

It was tedious! At one point I remember one of the hosties being in the flight deck and getting another of her colleagues to walk up and down the cabin with a catering trolley. She was amazed at the affect and the input required to maintain altitude.

It probably wasn't the comfiest of flights for our passengers!

Jonty
30th Jan 2016, 20:35
Do a google for Airbus Saftey First issue 20. Large article on manual flight at high altitude.
Some of it may surprise you.