View Full Version : Touch and Go
Groundbased
21st Oct 2011, 10:17
I was at East Midlands the other day and a Ryanair 737 was on a training pattern performing touch and go.
I wondered what the procedure is for this. Do you touch down with landing flaps and then retract them on the roll until its time to go again, or do you land with less flaps than normal and leave them set as they are until liftoff?
Curious is all.
gorter
21st Oct 2011, 11:20
You land with normal flap (whatever that may be on the 737ng not sure)
Only other change on approach is that the speed and auto brakes are not armed.
the following is company, base checker specific i'm sure but in general.
Student maintains the centre line does not deploy reverse. If either speed brake or thrust reverse is deployed then a/c brought to a full stop
base checker:
brings up the thrust to an intermediate level
retracts flaps to a take off setting
sets trim to a sensible amount
ensure speed brake is still down
checks engine instruments
brings thrust up to a take off setting.
Once all this is completed you should be at or near Vrotate
go again (minimum 6 if first type, 4 if experienced)
If anything goes wrong, base checker takes control and stops the take off.
Most fun you can have with your clothes on as far as i'm concerned
flyingtincan
21st Oct 2011, 16:50
What is the purpose of these particular touch and goes?
– is it to teach a landing followed (quickly) with a take off?
(and after a couple of good ‘uns does the ‘base checker’ get out and you do it on your own?)
– Or is for airport familiarisation?
– Or is it neither of theses?
– And yes it must be good fun.
barit1
22nd Oct 2011, 01:11
Touch & go is to give practice in approaches and landings - especially crosswind landings. The "go" part minimizes wear & tear on brakes, engines, thrust reversers, etc.
737NG...land with F15....then go with F15...the flaps run too slowly!
Denti
22nd Oct 2011, 07:46
Depends on country of AOC though. Flaps 15 on the 737 is not certified as normal landing flaps setting within JAR, so you have to take at least flaps 30. Lowest take off flap setting is 25 though, but usually 5 is used.
kenparry
4th Nov 2011, 15:14
What is the purpose of these particular touch and goes?
– is it to teach a landing followed (quickly) with a take off?
(and after a couple of good ‘uns does the ‘base checker’ get out and you do it on your own?)
– Or is for airport familiarisation?
– Or is it neither of theses?
– And yes it must be good fun.
Purpose: usually to complete type rating training. The student will not see any more until he either changes type (but he might do the whole TR training in a sim) or becomes a base trainer himself.
Base checker get out? No!
Airport famil: no.
fireflybob
4th Nov 2011, 16:16
737NG...land with F15....then go with F15...the flaps run too slowly!
All the touch and goes I have ever done/seen have been with flap 30/40 and flap 15 selected after touchdown - ok if the runway is long enough!
What is the purpose of these particular touch and goes?
Apart from giving (new) pilots practice at take off and landings on the real machine after the simulator (which in turn is a requirement for type rating etc), one purpose is to save time! If you landed and then taxied back to the take off point it would take a lot longer and also you can cool the brakes down a bit by leaving the gear down every so often in the circuit!
All the touch and goes I have ever done/seen have been with flap 30/40 and flap 15 selected after touchdown - ok if the runway is long enough! I have to assume that EW has never done any 737 base training, the object of which is to.....err...............learn how to land the 737 with normal flap settings, ie 30/40:D
Runway length is by no means crucial and it doesn't matter what the flaps are passing through when you rotate, although it is normally near to 15.
Nicholas49
4th Nov 2011, 17:10
Sorry, I have to ask. Why does it not matter what the flap setting is at rotate speed on a touch and go?! Is it not the same as a standard take-off, i.e. V speeds, climb performance etc. vary depending upon the exact flap setting?
One other question, what happens with the FMC? Can it be programmed for a touch and go so it transitions to a new departure while still on the runway?
NigelOnDraft
4th Nov 2011, 17:40
One other question, what happens with the FMC? Can it be programmed for a touch and go so it transitions to a new departure while still on the runway?I know nothing about the 737, so no idea what it does. Probably goes into a "GA phase"?
However, by definition you are flying visual circuits. Not a lot of need for an FMC. Look out of window.
NoD
Sorry, I have to ask. Why does it not matter what the flap setting is at rotate speed on a touch and go?! Is it not the same as a standard take-off, i.e. V speeds, climb performance etc. vary depending upon the exact flap setting? - never a problem, N49 - always welcome. (737) Approach speed at Flap 30 or 40 is pretty much the same as the required speed for climb away after take-off at F15. By the time the a/c is actually climbing away the flap have reached F15. Up to that point it may be more, but this is not a problem for handling since the speeds used will be safe (ie higher than for the greater Flap setting. Actual take-off and climb performance on this sequence of T&G's is not a problem since the weather will be good and there will be no problem obstacles in the flight path. For 'normal' ops you are absolutely right - "climb performance etc. vary depending upon the exact flap setting?"
One other question, what happens with the FMC? Can it be programmed for a touch and go so it transitions to a new departure while still on the runway? - no, never used since the pattern is flown visually ie no 'departure' as you post. Apart from using the FMC to determine approach speeds it will not be used.
NB I stand to be corrected when the first 'Child of the Magenta Line' reaches Base Training Cpt status and cannot, of course, fly a visual circuit unless it is programmed in the .............................................aaah! Stop me! Nurse!:)
Remember, F15 is a normal landing flap setting outside of europe. Seems to be a certification issue, probably due to approach category concerns.
Fieldmouse
5th Nov 2011, 00:53
Runway length is by no means crucial and it doesn't matter what the flaps are passing through when you rotate, although it is normally near to 15.
RAAF 737 BBJ happy to touch and go where I am, off the ILS, or land normally, but the 737 based Wedgetail AWAC reckons we aren't long enough at 7200ft. May have something to do with the squillion of dollars worth of gadgetry attached though?
Maybe the food/allowances/'friends' are better elsewhere? 7200' I would have thought enough. Can it normally operate at your house?
Nicholas49
5th Nov 2011, 11:56
Right, I understand re. the FMC / visual flying. Point taken.
But am still a bit confused on the V speeds front. BOAC, you say:
Approach speed at Flap 30 or 40 is pretty much the same as the required speed for climb away after take-off at F15.
Does this mean there is not a specific Vr for a touch and go?
It seems from what has been said above that it is acceptable and safe to rotate the aircraft while the flaps are in transit. But I have read here before that changing the flaps while on the take-off roll (e.g. if you realise they are not set correctly) is absolutely verboten in normal/revenue operations. So, do I understand correctly that a different set of rules apply for touch and go training flights?
Another thing (!): what happens about braking? Presumably you do not arm the autobrakes on the approach and when you land you simply let the aircraft maintain its speed? If, however, the training captain decides that a stop is (for whatever reason) required, would you have to brake manually?
Does this mean there is not a specific Vr for a touch and go? - in general the speed will be well above the required Vr (F15) (less than Vref F30) since very little time is normally spent actually on the runway once the thrust levers have been closed and the nosewheel is down, the throttles have been opened again and power is up. Most BTCs will have a figure in their heads, however, as a 'minimum'.
It seems from what has been said above that it is acceptable and safe to rotate the aircraft while the flaps are in transit. But I have read here before that changing the flaps while on the take-off roll (e.g. if you realise they are not set correctly) is absolutely verboten in normal/revenue operations. So, do I understand correctly that a different set of rules apply for touch and go training flights? - yes. In normal Ops it should be a 'stop' call.
Another thing (!): what happens about braking? Presumably you do not arm the autobrakes on the approach and when you land you simply let the aircraft maintain its speed? - no autobrake and no auto-spoiler (and no reverse). The a/c will slow a little with throttles closed. If, however, the training captain decides that a stop is (for whatever reason) required, would you have to brake manually? - yes, and deploy the spoilers and reverse (if desired).
It is important to remember also that these exercises are carried out at a relatively low weight - max of 7/8 crew. no pax, no c/c, little fuel, so performance should not be an issue (unless you are in a ' 737 based Wedgetail AWAC' and you want to go and visit the floozie at that airfield with a bigger runway/better crew diner/better allowances:).
Avionker
5th Nov 2011, 13:20
But I have read here before that changing the flaps while on the take-off roll (e.g. if you realise they are not set correctly) is absolutely verboten in normal/revenue operations. So, do I understand correctly that a different set of rules apply for touch and go training flights?
In normal/revenue ops I would expect that if the flaps were found not to be set correctly during the take off run then it would be more likely that not enough flap was deployed, as opposed to too much.
fireflybob
5th Nov 2011, 13:50
So, do I understand correctly that a different set of rules apply for touch and go training flights?
Depends what you mean by the word "rules".
Firstly, you're only legally obliged to obey the performance criteria on a revenue flight (which crew training is not).
On a revenue flight if you advance the thrust levers and get a take off configuration warning then the take should be rejected and you would proceed in accordance with company rules. Either way the take off flap setting should not be changed during the take off roll.
However, with respect to flaps, the TOWC will only sound if flaps are not in the take off range (for the B737 1 thru to 25) - I'd have to check the manuals but I think it's the selected setting rather than the actual but no doubt someone here will correct me on that if wrong!
A training flight is one that is operated in accordance with special procedures as laid down by the Company operations manual (including obviously advice from the manufacturer) - you also have a training captain in charge and more often then not a Safety Pilot in the jumpseat to assist and monitor.
Nicholas49
8th Nov 2011, 08:08
Thanks for the replies, gents. All clear now.
Just one more question. BOAC: you say there may be 7/8 crew members on such a flight. Can you train several cadets coming onto the line in the same touch-and-go flight, or is it normal to have one Training Captain and one cadet where the same cadet gets to performs the multiple touch-and-goes?
In my experience 6 co-pilots is about all the BTC's nerves can take:)
Add a 'safety pilot' on the jump seat to assist the BTC with many things and you have around 7-8.
Each co will get (in my experience and hopefully:D) around 6 landings, the last a 'proper' one to a 'stop' and taxy around for the next victim to take the seat. It is a longish day when you add on any transit to and fro and refuelling etc.
Nicholas49
8th Nov 2011, 19:09
Thanks, BOAC. Yes, I can imagine his nails are somewhat shorter that evening.
Out of interest: do the other cadets sit in the cabin while their contemporary flies, waiting their turn? I imagine it might be useful to experience how well (or not!) others do it?
One more (!) question: the OP said that he saw the touch-and-go circuit being flown at East Midlands Airport. That's a fairly busy airport with plenty of commercial traffic. In order to carry out these touch-and-go circuits at such airports, is it necessary to 'book a slot' with ATC? Do ATC have to find a 'quiet time' for you to do it? Or can such flights be flown with other traffic arriving and departing?
1) Yes - better not to have your mates creasing themselves up with laughter, looking over your shoulder, at your feeble attempts to land, and anyway with a jump-seat safety pilot there is nowhere else really to strap in.
2) Yes - can extend the day somewhat, but ATC at these airfields are normally pretty good and flexible. Airlines often find alternative little havens of peace with little traffic who just LURV the landing fees.