Robin DR400/180 stick back at start of the roll
Thread Starter
Join Date: Jun 2015
Location: Günzburg, Germany
Posts: 41
Likes: 0
Received 0 Likes
on
0 Posts
Robin DR400/180 stick back at start of the roll
Hi all,
I've recently changed my ATO and now will be trained either Grob or Robin. I already had a flight in Robin, where the instructor showed me something that I've not done before: holding the stick in back position form the start on the runway.
Earlier in Piper, I had to hold the forward pressure to keep the nose down until 60kts ('air speed live') and at 70 kts take off.
Somehow I forgot to ask the FI why he told me to hold the stick back. I will ask him the next time. But meanwhile, if you know it'd be great to learn from thoughts.
I should mention that it is a short 480m of grass runway.
I've recently changed my ATO and now will be trained either Grob or Robin. I already had a flight in Robin, where the instructor showed me something that I've not done before: holding the stick in back position form the start on the runway.
Earlier in Piper, I had to hold the forward pressure to keep the nose down until 60kts ('air speed live') and at 70 kts take off.
Somehow I forgot to ask the FI why he told me to hold the stick back. I will ask him the next time. But meanwhile, if you know it'd be great to learn from thoughts.
I should mention that it is a short 480m of grass runway.
Join Date: Feb 2009
Location: Do I come here often?
Posts: 898
Likes: 0
Received 0 Likes
on
0 Posts
Ouch! The Piper technique may give an extra shove upwards on rotation, but loading the nose leg like that is asking for future big trouble.
I haven't flown a DR400 for some time, but I was taught at Sywell back in the mists of time by Andre Baldet to start with the stick back and then relax the back pressure.
I'm probably way out on both counts, and have caused lots of damage as I went along.
I haven't seen a PA28 POH for years, and would be very interested if the hold it down technique is in there.
SND
I haven't flown a DR400 for some time, but I was taught at Sywell back in the mists of time by Andre Baldet to start with the stick back and then relax the back pressure.
I'm probably way out on both counts, and have caused lots of damage as I went along.
I haven't seen a PA28 POH for years, and would be very interested if the hold it down technique is in there.
SND
Join Date: Aug 2003
Location: Not a million miles from EGTF
Age: 68
Posts: 1,579
Likes: 0
Received 0 Likes
on
0 Posts
The DR400 is a lovely machine and strong. But as with all nosewheel aircraft you should lighten the load on the nosewheel. Too many pilots think their aircraft is indestructible and cause damage to the gear and engine mount - the Shoreham webcam is a great tool to see the abuse of training aircraft......
Join Date: Feb 2003
Location: Oxford
Posts: 2,042
Likes: 0
Received 0 Likes
on
0 Posts
Well, the POH for our club PA28 says 'The take-off performance ... is based on a take-off speed of 78 MPH IAS (68 Kts IAS). Accelerate the airplane to this airspeed and rotate.' That's all the advice they give, although the term 'rotate' could be said to preclude holding the stick back for the whole takeoff roll.
Thread Starter
Join Date: Jun 2015
Location: Günzburg, Germany
Posts: 41
Likes: 0
Received 0 Likes
on
0 Posts
Ooops ... my mistake. For Piper, it was 50 air speed alive, 60 take off, 70 climb ...
However, my question is about holding the control column back. Is it something specific to Robin?
Looking at your responses, it seems like a common technique taught for all the aircrafts. Is that so?
However, my question is about holding the control column back. Is it something specific to Robin?
Looking at your responses, it seems like a common technique taught for all the aircrafts. Is that so?
Join Date: Jan 2008
Location: Canada
Posts: 631
Likes: 0
Received 0 Likes
on
0 Posts
Earlier in Piper, I had to hold the forward pressure to keep the nose down until 60kts ('air speed live') and at 70 kts take off.
Yes, hold the stick either all the way back, or at least effectively nose light, through the entire take off ground roll. PA-28's can be a little troublesome if forces off the ground too early, but any airplane would rather have the third wheel light during take off. The only exception to this are some T tailed aircraft (Tomahawk) which are better accelerated nose neutral.
Letting along the immense wear and loading being imposed on the nosewheel when it is forced down, you are setting yourself up for a wheelbarrow of the whole plane. If the mains come off before the nosewheel, the aircraft could groudloop around the nosewheel. If in doubt, search Youtube for "groundloop", and then imagine that happening to you at takeoff speed.
Every Cessna tricycle single I fly will start the takeoff with my holding the stick fully back, until the nose has come up noticeably, and then held there until it flies itself off. My technique will be similar in every other tricycle I fly, though maybe not full nose up stick held in, just enough to lighten the nose.
The notion of a rotate speed in a flight manual is a little "big airplane dreaming", during the writing. If the nose is held light, and at the right attitude, most planes will fly themselves off nicely when they are ready. The actual "rotate" is more to assure that by that speed, you are airborne (as there is not reason not to be - unless something is wrong!).
You fly the plane, it does not fly you!
Join Date: Jul 2012
Location: Scotland
Posts: 158
Likes: 0
Received 0 Likes
on
0 Posts
I imagine the PA28 POH was written with the expectation of a hard runway, whereas the OP mentioned grass.
On grass particularly I'd expect appropriate technique to lighten the nose leg as early as possible. Conversely, I'd expect tailwheel technique to be the reverse to lighten the tailwheel as early as possible.
On grass particularly I'd expect appropriate technique to lighten the nose leg as early as possible. Conversely, I'd expect tailwheel technique to be the reverse to lighten the tailwheel as early as possible.
I was taught to keep the stick fully back during taxi AND when beginning to roll. The reason being indeed to reduce load and stress on the nosewheel and whatever carries it.
And keep it back and back until the nose wheel lifts off, from then on keep the nose pointing up as much as it does during initial climb-out. When all three wheels are off, push a bit more forward to gain some speed and retract flaps.
This is about a three-axis microlight, a typical 80 HP Rotax-powered two-seater. Mostly operated from grass. But I can see no reason to operate heavier planes differently, nor why a hard runway should make any difference. The philosophy of take-off is to be as high as possible as soon as possible, to have maximal options when the engine quits. All the while avoiding stalling, of course, by keeping sufficient airspeed.
And keep it back and back until the nose wheel lifts off, from then on keep the nose pointing up as much as it does during initial climb-out. When all three wheels are off, push a bit more forward to gain some speed and retract flaps.
This is about a three-axis microlight, a typical 80 HP Rotax-powered two-seater. Mostly operated from grass. But I can see no reason to operate heavier planes differently, nor why a hard runway should make any difference. The philosophy of take-off is to be as high as possible as soon as possible, to have maximal options when the engine quits. All the while avoiding stalling, of course, by keeping sufficient airspeed.
Join Date: Mar 2008
Location: In Exile...
Posts: 332
Likes: 0
Received 0 Likes
on
0 Posts
I aerotow with a DR400/180R and have about 50hrs (including most of my PPL) done on a PA28.
Keeping the stick back on a PA28 for that long is uncomfortable at best. You should be able to feel the aircraft starting to unstick. If you're on a tarmac runway, start with the stick in the middle and "check" back on the yoke at 60ish kts.
Brief for aerotowing in the DR400 is start with the stick on the back stop and as it starts to unstick, relax the back pressure so it flies off in a 3 point attitude - then once accelerated in ground effect to climb speed ease into the climb.
Enjoy the robin, they're lovely.
Keeping the stick back on a PA28 for that long is uncomfortable at best. You should be able to feel the aircraft starting to unstick. If you're on a tarmac runway, start with the stick in the middle and "check" back on the yoke at 60ish kts.
Brief for aerotowing in the DR400 is start with the stick on the back stop and as it starts to unstick, relax the back pressure so it flies off in a 3 point attitude - then once accelerated in ground effect to climb speed ease into the climb.
Enjoy the robin, they're lovely.
Join Date: Jul 2010
Location: in front of comptator :-)
Age: 65
Posts: 137
Likes: 0
Received 0 Likes
on
0 Posts
Ooops ... my mistake. For Piper, it was 50 air speed alive, 60 take off, 70 climb ...
However, my question is about holding the control column back. Is it something specific to Robin?
Looking at your responses, it seems like a common technique taught for all the aircrafts. Is that so?
However, my question is about holding the control column back. Is it something specific to Robin?
Looking at your responses, it seems like a common technique taught for all the aircrafts. Is that so?
However I move the stick forward quite a bit on every take off. But I'm flying a tail dragger. If I had stick full forward to that speed I would not get airborne as my prop would be digging the runway up. Also full back for more than about 3 seconds would result in a rapid lift off followed in a few seconds by a crash.
Thread Starter
Join Date: Jun 2015
Location: Günzburg, Germany
Posts: 41
Likes: 0
Received 0 Likes
on
0 Posts
Good that I asked this here. It seems I have unintentionally learned a bad habit and my FIs didn't notice. I'll definitely work on getting it right.
Keeping the control backward, wouldn't that mean that the aircraft could get off the ground even at a lower speed. A take off speed, I understand, is desirable for the sake of better control.
Keeping the control backward, wouldn't that mean that the aircraft could get off the ground even at a lower speed. A take off speed, I understand, is desirable for the sake of better control.
Join Date: Sep 2011
Location: Mare Imbrium
Posts: 638
Likes: 0
Received 0 Likes
on
0 Posts
I was taught to imagine that the nose wheel is made of glass - and to try to keep the load off it as much as possible: in any light aeroplane (though I dare say there will be exceptions (there always are) but it wouldn't be a PA28).
Keeping the control backward, wouldn't that mean that the aircraft could get off the ground even at a lower speed
Join Date: Oct 2014
Location: with bosun Blue Sky and the jenny haniver "Hot Stuff"
Posts: 106
Received 0 Likes
on
0 Posts
I am a super fan of Budd Davis over at Airbum.com whose article on the subject I found illuminating. Here it is - How Short is it Really?
If you don't want to read it all, here is the most pertinent section:
"The procedure is fairly cut and dried but does entail just a few nuances calling on you to really see what’s happening in the windshield.
We’ll start the takeoff (we’re assuming a tri-gear airplane) as we normally would, but, as soon as the airplane is rolling fast enough that we sense some life in the elevators, we position the yoke aft of neutral and hold it there. What we’ve done is insert a nose-up command in the elevator before the airplane has enough speed to pick the nose up. Then, when the airplane accelerates through the speed required to unstall the tail and pick the nose up, we immediately release some backpressure. At the same time, we look over the nose and visually fixate on where the nose is in relation to the horizon and, from that point on, our entire focus is to hold the nose in that position
Because the airplane is accelerating, if we don’t release back pressure and set a given nose attitude, the nose will continue coming up as the airflow over the tail increases with speed. What we’re trying to do is establish a slightly nose up attitude that positions the nosewheel something like six inches off the ground. Our goal is to hold that attitude firm, which will require us to gradually ease off the backpressure as the airplane accelerates. The first few times you do it, it’ll be a little counter intuitive because we’re actually moving the yoke forward slightly as the airplane takes off. The name of the game, however, is to use the nose like a rifle sight and absolutely nail it on a given position on the horizon and hold it there no matter what.
The net result of this little exercise is that the nose will come up, the airplane will run on the mains for a few seconds and will lift off when, and only when, the lift/speed curves cross and exactly match the environment in which the airplane is operating. It’ll compensate for every single thing having to do with the takeoff and won’t leave the ground until every factor is right. This is an instance where we can’t possibly know as much as the airplane does in terms of what is needed at that precise moment, in that precise location, with that specific airplane to safely leave the ground and be guaranteed of a positive rate of climb."
If you don't want to read it all, here is the most pertinent section:
"The procedure is fairly cut and dried but does entail just a few nuances calling on you to really see what’s happening in the windshield.
We’ll start the takeoff (we’re assuming a tri-gear airplane) as we normally would, but, as soon as the airplane is rolling fast enough that we sense some life in the elevators, we position the yoke aft of neutral and hold it there. What we’ve done is insert a nose-up command in the elevator before the airplane has enough speed to pick the nose up. Then, when the airplane accelerates through the speed required to unstall the tail and pick the nose up, we immediately release some backpressure. At the same time, we look over the nose and visually fixate on where the nose is in relation to the horizon and, from that point on, our entire focus is to hold the nose in that position
Because the airplane is accelerating, if we don’t release back pressure and set a given nose attitude, the nose will continue coming up as the airflow over the tail increases with speed. What we’re trying to do is establish a slightly nose up attitude that positions the nosewheel something like six inches off the ground. Our goal is to hold that attitude firm, which will require us to gradually ease off the backpressure as the airplane accelerates. The first few times you do it, it’ll be a little counter intuitive because we’re actually moving the yoke forward slightly as the airplane takes off. The name of the game, however, is to use the nose like a rifle sight and absolutely nail it on a given position on the horizon and hold it there no matter what.
The net result of this little exercise is that the nose will come up, the airplane will run on the mains for a few seconds and will lift off when, and only when, the lift/speed curves cross and exactly match the environment in which the airplane is operating. It’ll compensate for every single thing having to do with the takeoff and won’t leave the ground until every factor is right. This is an instance where we can’t possibly know as much as the airplane does in terms of what is needed at that precise moment, in that precise location, with that specific airplane to safely leave the ground and be guaranteed of a positive rate of climb."
Join Date: Sep 2006
Location: 23, Railway Cuttings, East Cheam
Age: 68
Posts: 3,115
Likes: 0
Received 0 Likes
on
0 Posts
Those lift off speeds for the PA28, I'm assuming a Warrior, that have been mentioned seem excessively high, I would expect to be airborne at 55 knots or thereabouts although I would unstick an Arrow at a slightly higher speed.
Unless I'm on tarmac/concrete I always hold full back stick/yoke when taxiing in or out in a trike and have back pressure (rather than a large movement) on the take off roll for the aforementioned less stress on the nosewheel reasons. Although for sticky/long grass fields I would use whatever technique the POH for that particular aircraft stated.
Re holding back the stick, I seem to remember the mighty Phantom was full back stick on the take off roll.
Unless I'm on tarmac/concrete I always hold full back stick/yoke when taxiing in or out in a trike and have back pressure (rather than a large movement) on the take off roll for the aforementioned less stress on the nosewheel reasons. Although for sticky/long grass fields I would use whatever technique the POH for that particular aircraft stated.
Re holding back the stick, I seem to remember the mighty Phantom was full back stick on the take off roll.
Join Date: Jan 1999
Location: north of barlu
Posts: 6,207
Likes: 0
Received 0 Likes
on
0 Posts
Adult supervision needed.
Any one who holds the stick forward on a PA28 take off roll should not be let out without a grownup to look after him, those above have well detailed the reasons.
It sounds to me as if your former instructor is a wannabe airline pilot, forward pressure on the stick up to 80 KTS is a Boeing 737 thing to keep nose wheel steering authority untill the rudder gets some airspeed.
I would guess I am looking at about 1000 hours of DR400 time and the best way to get the aircraft off the ground on grass is to hold he stick full aft at the start of the take off run and as the airspeed increases past around 30 KTS smoothly move the stick forward to a position just aft of neutral, then at about 50 KTS move START a smooth rotation.
This assures minimum load on the nose gear and moving the stick forward after 30 KTS keeps the same nose gear protection due to the increasing effectiveness of the Stab due to increased airspeed but reduces drag and the risk of getting the aircraft into the air below the normal stalling speed due to ground effect.
Enjoy the DR400, it is without doubt the best aircraft in its class.
It sounds to me as if your former instructor is a wannabe airline pilot, forward pressure on the stick up to 80 KTS is a Boeing 737 thing to keep nose wheel steering authority untill the rudder gets some airspeed.
I would guess I am looking at about 1000 hours of DR400 time and the best way to get the aircraft off the ground on grass is to hold he stick full aft at the start of the take off run and as the airspeed increases past around 30 KTS smoothly move the stick forward to a position just aft of neutral, then at about 50 KTS move START a smooth rotation.
This assures minimum load on the nose gear and moving the stick forward after 30 KTS keeps the same nose gear protection due to the increasing effectiveness of the Stab due to increased airspeed but reduces drag and the risk of getting the aircraft into the air below the normal stalling speed due to ground effect.
Enjoy the DR400, it is without doubt the best aircraft in its class.
Join Date: Feb 2007
Location: Amsterdam
Posts: 4,598
Likes: 0
Received 0 Likes
on
0 Posts
Specific for the DR400 (and R2160 too, btw), there is one other thing to consider.
The nose wheel is spring loaded and when there is no or virtually no weight on the nose wheel, it will "lock" in the dead ahead position. This is to reduce aerodynamic drag while in the air.
On the ground, particularly after an extremely soft landing, it is possible that the load on the nosewheel is not yet high enough to disengage the nosewheel from the lock. This means you have no nosewheel steering, and may become a problem as the speed diminishes and you also lose aerodynamic (rudder) steering.
For this reason you may want to put a little load on the nosewheel immediately after landing (check stick neutral or slightly forward of neutral). And it might also be something to be aware of when you do take-off with full stick back: You may just engage the lock before you have sufficient aerodynamic rudder authority.
The nose wheel is spring loaded and when there is no or virtually no weight on the nose wheel, it will "lock" in the dead ahead position. This is to reduce aerodynamic drag while in the air.
On the ground, particularly after an extremely soft landing, it is possible that the load on the nosewheel is not yet high enough to disengage the nosewheel from the lock. This means you have no nosewheel steering, and may become a problem as the speed diminishes and you also lose aerodynamic (rudder) steering.
For this reason you may want to put a little load on the nosewheel immediately after landing (check stick neutral or slightly forward of neutral). And it might also be something to be aware of when you do take-off with full stick back: You may just engage the lock before you have sufficient aerodynamic rudder authority.