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I'm a student pilot learning on a Piper Cherokee 180. When I land and the nose wheel touches down my instructor wants me to keep pulling back on the stick through the landing roll.

For soft field landings this makes sense as you don't want the nose wheel to dig into the ground and tumble over. However we are landing at an airport with hard surface runways which routinely experiences gusty wind conditions. It seems to me that if I keep pulling up and a gust of headwind hit us shortly after the nose wheel touches down that the gust would lift the nose wheel back off the ground. This of course would not be a good thing. So in my mind I think it would be better to ease off the back pressure once the nose wheel touches down. What are your thoughts?

Note: My instructor was a crop duster so I think he just carried over the soft field landing technique and is just teaching this because this is what he learned.

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    $\begingroup$ Keeping the flaps down and the nose up slightly lets the wings help slow the plane down. You don’t need to use the brakes as much (or at all). $\endgroup$ – JScarry Sep 6 '18 at 23:12
  • $\begingroup$ see aero braking aviation.stackexchange.com/questions/51834/… $\endgroup$ – Pilothead Sep 7 '18 at 4:04
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It is a soft field technique but is generally applied on hard surfaces for the sake of the aircraft. There are a few main reasons;

  1. Take stress of the nose wheel and nose gear assembly which is a bit more fragile than the main gear assembly. This is particularly true in aircraft equipped with a steerable nose wheel like the Cherokee (or in retracts).
  2. Provide adequate clearance for the propellor. If you look really closely the Cherokee has a low enough clearance such that, excess low pressure on the nose wheel and a sufficiently hard landing can cause a prop strike. This is one of the reasons its so important to check tire pressure in your preflight.
  3. It also helps to reduce the risk of the fated nose wheel bounce which can collapse the assembly.
  4. Generally it also helps to prevent you from simply releasing the controls after the mains touch down or potentially even pushing forward on the column which would drive the nose down and potentially cause damage.

During training this also helps to build habits that lead to a good landing attitude and speed bleed off especially if you start out landing flat.

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    $\begingroup$ While these are valid reasons, the practical effects of holding back after the nose is down are debatable. It's more important to put the nose down gently than to hold back pressure afterwards. It does help to reduce nose wheel shimmy; however, if you're getting that then your plane needs maintenance anyway. $\endgroup$ – Ralgha Sep 6 '18 at 21:31
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    $\begingroup$ I'm not an expert, but would pulling up also mean more drag, so you brake faster? As the airplane needs to spend energy to convert it into lift, that normally would be dissipated through ground contact $\endgroup$ – Ferrybig Sep 7 '18 at 9:19
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    $\begingroup$ As long as you aren't pitching up when pulling back it also means more down-force on the rear gear which improves braking performance. $\endgroup$ – ratchet freak Sep 7 '18 at 9:33
  • $\begingroup$ In that video, did the guy make a decision to go through with the landing? Or is this a weird aerodynamic situation where it's not possible to apply power and take off again? $\endgroup$ – Undo Sep 7 '18 at 16:27
  • $\begingroup$ @Undo this may be worthy of a separate question but its always hard to say what decision he made. Its clear he made the decision not to apply full power and execute a go around which he should have. $\endgroup$ – Dave Sep 7 '18 at 16:28
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Aerodynamic slowing is more effective than wheel-braking at touchdown speeds, and aerodynamic directional control is more effective than pedal steering until you decelerate enough that you can't keep the nosewheel in the air. If you're flying a differential-steering (or "brake-steering") airplane, this is even more important. Using this technique, you would push forward to neutral elevator once the elevator loses effectiveness, so the headwind gust should not affect you much. Even with your nosewheel on the ground, if you experience a gust, you'll still need to "fly" the airplane (remember the taxiing rules). Any time you have all 3 wheels on the ground, you're taxiing (even if you're on the runway). If you keep the mindset that you are "flying" all the time, then you're unlikely to lose control when you encounter a gust or wake turbulence.

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    $\begingroup$ And holding the elevator up helps with wheel braking as well, as it shifts the aircraft's weight from the nosewheel to the main gear (where the brakes are). $\endgroup$ – Sean Sep 7 '18 at 3:18
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    $\begingroup$ @Sean This is a myth. Apart from a prang, the nosewheel at most has ten percent of aircraft weight on it. Any action that would reduce that weight will increase wing angle of attack, creating more lift than what could be theoretically transferred to the mains. Back pressure on the stick on landing is useful for aero braking, as the answer states. $\endgroup$ – Pilothead Sep 7 '18 at 3:45
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Other answers have covered the tricycle gear situation well - and of course that's what you're flying - but you mentioned that your instructor was a crop duster and it's possible that he's carrying over some tailwheel technique into your training.

In a tailwheel aircraft, it's normal to keep the stick fully back throughout the landing roll and even during taxiing to get more weight on the tailwheel and improve directional control on the ground as the airspeed bleeds off and the rudder loses control authority (see this question). Many crop dusting aircraft are tailwheels, and it may be that your instructor is doing it out of force of habit.

I'd suggest just asking him about the technique - in a neutral way! - and see what he says.

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    $\begingroup$ "as him about the technique" as in "This seems counter-intuitive to me (for reasons in OP) - can you explain further the reasons for it so I'm not confused." $\endgroup$ – FreeMan Sep 7 '18 at 14:42
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This has been alluded to in a comment, but to put it in an actual answer: one of the primary reasons for holding the stick back during rollout on a tricycle configuration such as the Cherokee is increased brake effectiveness. Holding back the stick causes more of the weight to be born by the main gear rather than the nose gear. The main gear have brakes. The nose gear does not. Therefore, putting more of the weight on the main gear makes the brakes more effective.

Additionally, prior to the nose gear touching down, holding the nose high after the mains touch down causes much more drag, too. This is known as aerobraking and is a quite effective method of slowing down the aircraft. Aside from helping to slow the aircraft more quickly, aerobraking is also beneficial due to the fact that it dissipates the aircraft's energy into the air (which doesn't wear out) instead of into the brakes (which do wear out and are expensive to replace.)

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  • $\begingroup$ And from a comment on that comment: This is a myth. Apart from a prang, the nosewheel at most has ten percent of aircraft weight on it. Any action that would reduce that weight will increase wing angle of attack, creating more lift than what could be theoretically transferred to the mains. Back pressure on the stick on landing is useful for aero braking, as Roberto's answer already states. $\endgroup$ – Pilothead Sep 7 '18 at 3:49
  • $\begingroup$ @Pilothead Increase in AoA once the nose gear is down would be relatively minimal. It would only be from less strut compression on the nose gear. And what AoA increase did exist would also add to aerobraking. More importantly, holding the stick back means the elevators/stabilators will be deflected to cause a downward force on the tail. This will add to the force on the mains and does indeed increase braking effectiveness. Granted, all of these effects will diminish rapidly once the tail stalls, but that will happen after the wings stall. $\endgroup$ – reirab Sep 7 '18 at 4:09
  • $\begingroup$ The strut has 4in of travel on a 90in wheelbase. Unloading the strut results in a 2.5deg increase in angle of attack. At any speed where the tail is still capable of raising the nose, the increased wing lift will exceed the 200lb max you can unload from the nosewheel. As I said, I agree with aerobraking. $\endgroup$ – Pilothead Sep 7 '18 at 4:45
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Short answer, listen to your instructor.

Next, evaluate the landing sequence and what it would take to lift your plane off the runway after it touches down. You will note that at approach speed and when you flare, the AOA to stay in the air is much higher than after your nose wheel is down.

The only time there would be a significant risk of being lifted back into the air would be when the mains were down and the nose was still up. Here your question is very valid and you may wish to work out a procedure with your trainer to deal with this.

A bounce when you land is a similar situation, airspeed still a little high. Uber important to land on the much stronger mains and keep flying the plane as it settles onto the runway.

Aside from what are you doing flying in that type of weather, part of your plan could be to initiate a full power - go around if you get lifted more than a few feet.

If your procedures allow, you may also consider immediately retracting flaps as soon as your nose is down to further lower your AOA to a headwind gust.

But under normal conditions holding the nose off on your roll out will reduce stress on the nose wheel and give a little more aero braking.

Yes, if your nose rises unacceptably, it is good to relax back pressure on the stick, practice will help one know how much.

Bob

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When the nose is pulled up, it increases the reaction on the main wheel. The braking friction force is given as Friction = (braking friction coefficient) * reaction Therefore, by pulling the nose up, you are increasing the friction and there will be a reduction in the stopping distance.

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Your instructor was likely taught, as I was that the nose wheel is as fragile as a twig and that you need to keep pressure off it at all times. In reality there isn't that much pressure on it during a normal touch down and roll out. As a new pilot and wanting to be as proficient as possible I have videos of most of my landings (Piper 140) taken from the rear tie down facing forward. Even on the odd cough cough "firm" landing with full flaps the struts barely compress. Only a small percentage of the total weight isn't still being held up by lift at touch down. Most firm landings "feel" way worse that they really are. Even during roll out when the wheels are on the ground and speed is down near 40kts there is still tons of lift. When you dump the flaps, that's when the plane settles down to almost "normal rest" position on the struts. It's quite dramatic the drop. If the winds are light I almost always keep the flap down until I'm not reading airspeed any more. I also use back pressure as a very effective brake during the roll out. The point to my long winded response it that there are multiple ways to protect the nose wheel.

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  • $\begingroup$ Hi Chris. This is an interesting anecdote, but I'm not sure it answers the question at the top of the page. Please note that the Stack Exchange format is meant for a single question, and answers to that single question; not forum-style ongoing discussion. Answers that don't attempt to answer the question can be deleted by our experienced community member. Maybe you can Edit this to clarify how it addresses the original question? $\endgroup$ – a CVn Sep 10 at 13:56

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