Power first or flaps & trim?
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Power first or flaps & trim?
When conducting touch & go`s, do you teach setting power first (before setting flaps & trim) or the other way round. Grass strip, about 800 metres.
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We teach Touch & Go's retracting flap first (and making sure that they are moving) then apply full power. Once airborne readjust the trim once at the required climb speed. Reason being, in the 172 with Electric flaps they take time to retract unlike a lever operated flap system which is basically instant.
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You don't mention what type aircraft, but with a soft field I feel you might need to do things a bit different, my recollection on a paved strip was to change flap and trim prior to power.
A Touch and Go's does not exist as a stand alone maneuver. It is a normal landing followed by a normal takeoff. This means that like any takeoff the aircraft should be in the takeoff configuration (ie flaps set for takeoff and trim in the takeoff range) before full power is applied. If there is not sufficient time to reconfigure the aircraft in a calm and deliberate manner after it has touched down and control is assured before continuing with the "go" part of a touch and go then the field is too short.
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That`s what I thought. After an absence of 25 years as an Instructor, was shocked that the guy doing my check, told me to set the power first. Do that in the Airlines, and you would be in big trouble. Teaching good habits is priority no 1, and setting power before configuring the aircraft (c152) is looking for trouble I think!
If the runway is so short that you have to apply power to accelerate before configuring the aircraft, then conducting 'touch and goes' is probably not advisable, especially with electric flaps when an over eager student may attempt to get airborne whilst the flaps are still retracting, leading to the inevitable sink on departure....! I agree with configure first, then if sufficient runway remaining apply power.
I know the reasoning behind touch and goes is to give the student as much take off and landing practice as possible, but I wonder how many instructors also teach go around from the flare, or even go around after the main wheels are 'on' to simulate the situation where you have floated and have insufficient room to stop.
If the wheels are on the ground in the above simulated situation of not enough room to stop, do you then teach the 'go' as a go around in the landing configuration or do you raise flap to short field configuration (ie partial flap extended), then take off at minimum airspeed and climb at Vx?, or any other thoughts?
I know the reasoning behind touch and goes is to give the student as much take off and landing practice as possible, but I wonder how many instructors also teach go around from the flare, or even go around after the main wheels are 'on' to simulate the situation where you have floated and have insufficient room to stop.
If the wheels are on the ground in the above simulated situation of not enough room to stop, do you then teach the 'go' as a go around in the landing configuration or do you raise flap to short field configuration (ie partial flap extended), then take off at minimum airspeed and climb at Vx?, or any other thoughts?
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Firstly, I would teach to avoid getting into that type of situation in the first place.
Secondly (and we've had a rather heathed discussion about this before), I teach that a go-around is an unintended manoeuvre so the priority is to bang on the power, stop any descent/initiate a climb and then reconfigure.
Conversely, the 'go' bit of a T&G is an intentional take-off after a successful landing and therefore the pilot should be configuring for take-off before commencing the take off.
Secondly (and we've had a rather heathed discussion about this before), I teach that a go-around is an unintended manoeuvre so the priority is to bang on the power, stop any descent/initiate a climb and then reconfigure.
Conversely, the 'go' bit of a T&G is an intentional take-off after a successful landing and therefore the pilot should be configuring for take-off before commencing the take off.
This pops-up fairly regularly and usually demonstrates that there are two camps.
My opinion is that a touch and go is a useful training exercise that saves the student a considerable amount of time and money and only takes a very short time to learn, therefore it's appropriate to use and teach it. In the general case power should be increased first because doing otherwise results in being lower over the houses than necessary; it is also the same sequence used for a go-around so things are more consistent for the stude. If operating from a long runway the sequence is less critical but I believe it's still good to use the same sequence as for a go-around, unless coming to a full stop (in which case it's not really a T&G).
The nay sayers will now talk about distraction during the acceleration, but others will point-out that training aircraft will become airborne and climb with landing flap, and also that the record does not show it to be a risk. The nay sayers will also usually be operating from long runways whereas those that teach power first will operate from less than 800m.
HFD
My opinion is that a touch and go is a useful training exercise that saves the student a considerable amount of time and money and only takes a very short time to learn, therefore it's appropriate to use and teach it. In the general case power should be increased first because doing otherwise results in being lower over the houses than necessary; it is also the same sequence used for a go-around so things are more consistent for the stude. If operating from a long runway the sequence is less critical but I believe it's still good to use the same sequence as for a go-around, unless coming to a full stop (in which case it's not really a T&G).
The nay sayers will now talk about distraction during the acceleration, but others will point-out that training aircraft will become airborne and climb with landing flap, and also that the record does not show it to be a risk. The nay sayers will also usually be operating from long runways whereas those that teach power first will operate from less than 800m.
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Little story to add to the discussion: My chief pilot was practicing to get his qualification as a type rating examiner on the good old Shed (Shorts 330/360). He was conducting a 6 monthly base check on yours truly under supervision. The last manueuver was to be an assymetric ILS which went without a hitch from which I had been briefed to expect to land. At 200' I therefore declared runway in site and applied full landing flap. The descent continued but my chief pilot decided on an extra emergency so he called for a go around at 100'! Now, normally this is not done with full landing flap, so I opened the throttle to full climb power, applied the necessary rudder and wound the nose up to the usual climb attitude. As a result I watched my airspeed start to collapse! The nose was therefore eased down until said speed stabilised at an acceptable value with the nose a tad above the horizon. The good old shed with its one engine running, but fortunately empty staggered back to 500 feet and I could then look around and realised the problem. We flew a circuit, landed and said chief pilot was understandably very red faced as he received a debrief from the supervising examiner. Fortunately my license got signed for another six months of night freight duties.
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I'm not an instructor but..
I did all my training up to ME IR at an airfield with a relatively long runway. I was taught it was always flaps up then set power.
I've recently joined a club at an airfield with a short grass strip and was surprised to hear it's SOPs to set power then raise flaps.
I can see reasons why both are better depending on the situation to be honest.
I did all my training up to ME IR at an airfield with a relatively long runway. I was taught it was always flaps up then set power.
I've recently joined a club at an airfield with a short grass strip and was surprised to hear it's SOPs to set power then raise flaps.
I can see reasons why both are better depending on the situation to be honest.
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This is about instructing vs the real world.
A student is taught to retract flaps first, then as he adds power, he has a stable 'wing' to climb out on. Conversely, having a student add power first, could put him flying in ground effect pretty fast, then retracting flaps without adjusting decking angle, he could stall, hit the ground, etc.
In the real world, landing a jet, fuel truck pulls out on the runway...you add power first, to get the plane accelerating/flying, get up into ground effect ASAP and retract flaps to TO position, and get over the obstacle.
So this is about have the ability to adjust as the flaps are moving...a student can't, a pro can.
Without power the plane isn't going anywhere, and this question is quickly answered when you have an obstacle up ahead, and your decelerating rather then accelerating.
A student is taught to retract flaps first, then as he adds power, he has a stable 'wing' to climb out on. Conversely, having a student add power first, could put him flying in ground effect pretty fast, then retracting flaps without adjusting decking angle, he could stall, hit the ground, etc.
In the real world, landing a jet, fuel truck pulls out on the runway...you add power first, to get the plane accelerating/flying, get up into ground effect ASAP and retract flaps to TO position, and get over the obstacle.
So this is about have the ability to adjust as the flaps are moving...a student can't, a pro can.
Without power the plane isn't going anywhere, and this question is quickly answered when you have an obstacle up ahead, and your decelerating rather then accelerating.
You seem to be taking two totally different scenarios.
Your first is, aircraft on the runway, so retract flaps (ie configure for take off) then carry out a take off.
Your second scenario, I hope is meant to be a go around from low level where you would apply power, adjust pitch , reduce drag flap and carry out a missed approach. If, in a jet, you have landed and something pulls onto the runway, it is a brave man that applies power with landing flap selected and tries to take off from an unknown runway length! to avoid an obstacle.
Your first is, aircraft on the runway, so retract flaps (ie configure for take off) then carry out a take off.
Your second scenario, I hope is meant to be a go around from low level where you would apply power, adjust pitch , reduce drag flap and carry out a missed approach. If, in a jet, you have landed and something pulls onto the runway, it is a brave man that applies power with landing flap selected and tries to take off from an unknown runway length! to avoid an obstacle.
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Adding power first with flaps could cause sufficient lift to get airborne, then, as the flaps retract, the life coefficient is reduced enough that it cannot remain airborne, and touch down.
Better to reconfigure into your take-off configuration, then add power. Plus, during reconfiguration, if an error is detected it's far easier to stop, compared to at full pelt.
Better to reconfigure into your take-off configuration, then add power. Plus, during reconfiguration, if an error is detected it's far easier to stop, compared to at full pelt.
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To preface, I am not an instructor, and do not claim to have familiararity with training techniques. If pure training technique is the objective, mine may not be the best answer. However, in respect of electric flap aircraft (it's probably not an issue for manual flap aircraft) ...
If you have decided to go after your touch, and you're making that happen, the longer duration and distance you're spending on the runway, the more chance of a problem. Get going, and get back up. Toward that end, acceleration is your priority, get the power on. Yes, with full flap, the plane could get airborne right then, so be it! It could also, if take off flap were carefully set, and you were hit by a healthy gust. In either case, your duty is to maintain control of the plane, your duty is not so much to ride along up again in a prefectly configered and trimmed plane. If you can, great, but if not, you still have to fly it.
All certified aircraft have demonstrated three things in this regard. First, control forces will not become so great, that the pilot cannot maintain control. Secondly, the aircraft will fly, and climb away, regardless of the flap setting. Once climbing away, the flaps can be retraced all the way, and control and a climb maintained, without requiring unusual pilot skill. These are certification requirements.
If in an electric flap aircraft, you select from full to take off flap, and then wait and watch for that setting to be achieved while rolling along the runway at idle power, you're wasting runway, and allowing a hazardous distraction while on the runway. At least in the air, you have only to prevent landing again, of hitting obsticles, while you get the plane sorted.
A part of what is being discussed here is flying technique, but another part is decision making, and the background thinking....
If you have decided to go after your touch, and you're making that happen, the longer duration and distance you're spending on the runway, the more chance of a problem. Get going, and get back up. Toward that end, acceleration is your priority, get the power on. Yes, with full flap, the plane could get airborne right then, so be it! It could also, if take off flap were carefully set, and you were hit by a healthy gust. In either case, your duty is to maintain control of the plane, your duty is not so much to ride along up again in a prefectly configered and trimmed plane. If you can, great, but if not, you still have to fly it.
All certified aircraft have demonstrated three things in this regard. First, control forces will not become so great, that the pilot cannot maintain control. Secondly, the aircraft will fly, and climb away, regardless of the flap setting. Once climbing away, the flaps can be retraced all the way, and control and a climb maintained, without requiring unusual pilot skill. These are certification requirements.
If in an electric flap aircraft, you select from full to take off flap, and then wait and watch for that setting to be achieved while rolling along the runway at idle power, you're wasting runway, and allowing a hazardous distraction while on the runway. At least in the air, you have only to prevent landing again, of hitting obsticles, while you get the plane sorted.
A part of what is being discussed here is flying technique, but another part is decision making, and the background thinking....
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From a SEP training perspective this comes down to whether the 'Go' bit is planned or not. If it isn't, I would suggest that you want to 'Go' rather quickly and echo Pilot DAR's sentiments. Conversely, if you are just practising landings, the 'Go' bit is more measured and you should reconfigure before taking-off. The argument about whether you have enough time to do this is extremely valid; you should be deciding whether you have the capability/performance to carry out such an action before you get there.
One other word of warning. Personally I have had two students who applied power and then raised the flap. Both ended-up off the side of the runway as the aircraft got airborne/light on the wheels, directional control wasn't maintained whilst the student fumbled for the flap switch and the aircraft eventually dropped back on to the ground as the flaps were travelling.
Pilot DAR's point is extremely valid. Maintain control of the aircraft, everything else is secondary.
One other word of warning. Personally I have had two students who applied power and then raised the flap. Both ended-up off the side of the runway as the aircraft got airborne/light on the wheels, directional control wasn't maintained whilst the student fumbled for the flap switch and the aircraft eventually dropped back on to the ground as the flaps were travelling.
Pilot DAR's point is extremely valid. Maintain control of the aircraft, everything else is secondary.
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At my fto in the pa28 we are taught after touch down retract flaps to desired take off position (or even fully retract depending on conditions) then in with the power, get airborne then trim out.
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When conducting Airbus touch and go's, you also raise flaps before applying TOGA thrust (the trim is automatic.)
When going around in the Airbus, at the standard missed approach point, you apply TOGA thrust a split second before raising the flap lever one stage, the call being "Go-Around Flaps".
When going around in the Airbus, at the standard missed approach point, you apply TOGA thrust a split second before raising the flap lever one stage, the call being "Go-Around Flaps".
Adding power first with flaps could cause sufficient lift to get airborne, then, as the flaps retract, the life coefficient is reduced enough that it cannot remain airborne, and touch down.