How soon after take-off can one engage the autopilot
 

How soon can one engage the autopilot after take-off? What is the normal procedure?

A320 : autopilot can be engaged : at 30 ft AGL if Speed Reference System available, or 500 ft min. without speed guidance.

Hey Shon... Although I like your questions... I'm just wondering... writing a book or a filmscript or something?

P77 :confused:

Lets set the scene - FO doing his command training.

After 1st flight with training captain, debreifing starts and training captain thinks all is going well, however points out that after take off the sooner the a/p is engaged the better, gives you more time to keep an eye on instruments, freq changes etc.

Debreif after 2nd flight (with different training captain) has the opinion all is going well, however don't be so fast to engage the a/p - remember you are a pilot and an aviator, not a computer guy - fly the plane first and when all is well and established on climb out engage the a/p then.

Just before pushback with 3rd different training captain the up and coming FO asks "At what stage of the departure would you like me to engage the a/p Sir?"

3rd Training Captain reply "How in the hell do you expect to get a command if you dion't know when to engage the a/p".

Do I hear some personal frustration sipping through, BCP?

In my company we have a simple rule about engaging the autopilot on the A320: not before 100ft and only after 5 seconds after liftoff.

The rest is pilots discretion.

Think of a good reason to fly manually and fly manually; if you think you have a good argument to fly automatically, engage the a/p.

IMHO there is no standard rule about where to engage the a/p; it is situation-dependent. If the trainings captain has a good argument why to wait with the a/p, you could listen. Only stating "you're an aviator" is not a good enough reason for me.

Factors in deciding whether to engage earlier or not could be: weather (maybe you want to climb faster than is programmed), delay (speed up earlier than programmed), difficulty of departure (to keep an eye on tracking), noise abatement (a/p can or cannot follow the SID more exact than you depending on type of a/c) etc etc.

As an example of engaging earlier I take a Moscow-departure, where the PNF is busy changing frequencies, and you as PF can set the FCU, instead of, when flying manually, all the work to be done by the PNF.
An example of engaging later could be a regional airport with a lot of buildups in the departure path, and a very low amount of traffic.

I think the comment of your 3rd captain makes most sense of all: if you wanna be a captain, you'd better have an opinion!

P77

Settle down Pegasus 77,

This happened to a fellow pilot (friend) of mine many many years ago. He dined out on the story for years, and still does. It was related back to the three captains over the years, who all found it a good laugh at the end of the day.

My reply to the post was probably not in the correct section of the forum, I was trying to give a few a laugh with the lighter side of aviation.

Ah... well at least I took you seriously :D :D
Didn't read your post that way... sorry! :(

But I'll leave my post above unchanged, because it might answer the question of Shon7.
No hard feelings, bcp?!

P77

Hey Pegasus77 - Thanks for your replies. In response to your question - no I am not writing a book or a film script but these are questions that I have wanted to ask pilots for the longest time but never could. Also I have seen the books and resources around but have never been able to find these answers.

For example: when do you know how to flare a 747 and can you feel it etc- which I posted in the last post.

Thanks once again to everyone for all their replies. The questions will keep coming. In fact I think I will post one now.

Shon7..... there are two ways to flare a 747. One is to do it with visual cues and the other is to listen to the Radalt call out giving you feet above runway.
Oh I forgot the third method, when the other pilot flinches it is time to flare, the last usually gives a firm arrival!:D

Well, just ask the TriStar pilot...he (or she) can engage the autopilot on the ground (CWS) and then commence the takeoff....this is not possible with L1011 aeroplanes on the British register as the ARB (CAA) decided that this was not a good idea...which begs the question...what do they know about a US designed aeroplane....answers on a postcard.
Re-engineering the wheel comes to mind.
Minds stuck in the Trident mode.....:rolleyes:

To reply to the threads initial question,

B737-300:

Boeing:

* At 1000 ft AGL until 50 ft radar-alt at the destination/alternate airfield (single AP).

Company:

* Any time after aircraft is established in enroute climb or cruise and all checklists are completed, until -
i) published minimum
ii) 500 ft AGL for unpublished approaches but served by a destination nav-aid suitable for center-line tracking
iii)500 ft AGL (day) and 1000 ft AGL (night) for approaches with nil electronic approach aids
iv) At the circling minima whilst manouvering at certain Company airports (due close-proximity of high terrain)

at the destination/alternate airfield.

* Notwithstanding the above, at any time the PIC deems its use necessary in the interests of safety, crew workload or expedition.

Usual on-line practice:

AP in -

1. TOPC if climb uneventful and/or a low-level crz alt

2. During enroute climb if workload high or where feelin particularly lazey!

AP out-

1. TOPD if descent/approach anticipated to be uneventful with low/medium-workload

2. Co minimum as mentioned above if where feelin a little bit bloodey fragile that day!

B744 - 250 feet is minimum engagement height for a/p after takeoff.

737-300 A/P can be engaged at 500ft RA.

B757 has a CAA imposed restriction of 500' aal before autopilot engagement (I seem to remember Boeings limitation is 200') for take off. The 757 does not need to have the (coupled) autopilots taken out until the very end of the landing roll in order to vacate the runway.

If you haven't stuck your T* on the computer shortly after 300 feet you're a big girl's blouse. Admittedly that's just my personal opinion....

I call for zero flap at 400 feet AAL. Once it's away, I'll do me scans and engage the a/p before calling for after take-off checks. I find this spreads the workload very nicely, allowing me time to ascertain how much other traffic I need to thread me way thru.

If I'm feeling brave (only when there's little or no other traffic to contend with), I'll leave the a/p out to 10,000 feet.

For the descent, I usually take the a/p out at TOPD if the arrival is particularly awkward. But, if there's a lot of other traffic around, I'll leave it in because, no matter how awkward the arrival is, there'll be too many other aircraft blocking my descent. If I haven't disengaged it any sooner, I'll do so at the IAF or, if using a visual approach and a circuit, I'll disengage the a/p before manoeuvring to join the circuit.

A Kingair is pretty flexible tho and other circumstances can dictate the need for a different set of strategies...

L1011 - well lets see, it was a Brit. who wrote the definitive book on the auto flight system, approved by Lockheed, his name was Capt. Mike White, ex Court Line and it was the Brits who required about forty modifications to the basic B707 before it came onto the British register and Boeing adopted them all as standard,
oh, why should I go on, the list is endless!!!

On the B747-400 normally not before 400'agl. That is SOP rather than actual ability to engage.

Well said Twistedenginestarter

The 121 went a bloody sight faster than the 1011 too, but what would these Yanks know.

... and they had to offset the nosewheel on the Trident because the autoland was so accurate it would hit the centreline lights and worry the pax...

... and the Tristar autoland was developed by the Smith team, who went to Lockheed...

..and one of these days I'll find one of the real thing and be able to see what it does outide the sim :D :D :D :D :D

Final3

You're the right stuff!!

And don't worry about the sim thing. Some planes only live on in our (fading) memories. But they live on all the same....

I thought the Tristar was a lovely plane (not just because it started with a T) and am sad I never had a go on one.

Scottie just for my own benefit where do you get that the 737-300 AP is permited be engaged at 500 ft RA? Boeing says above 400 ft RA it is capable of being engaged but is your published Boeing Limitations diferent from mine?