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Jerico
3rd Jul 2007, 15:56
On a recent rainy day in the clubhouse we ended up with a discussion on taxying.
If you are taxying, for arguments sake, a Piper SuperCub downwind on a smooth taxi way with a short grass surface and a surface wind of 20kt gusting 30kt, should you hold the stick back or should it be held in a neutral position.
One point raised in the discussion was that when trained on Tiger Moths in 1960's, the training (at UAS) was to always keep the stick back. The instructors argument was to teach students to keep the taxying speed under control at all times and the stick back.
Always taxy slowly and the tail will not lift, if the aircraft should hit a bump or a dip while the stick is held in a neutral position there is more chance of the tail lifting and same applies if taxying too quickly.
So if the stick is held back in all conditions on a smooth grass surface, is there less chance of the aircraft ending on its nose?
I was taught to move the stick into a neutral position when taxying downwind in a strong wind, but I am now thinking that holding the stick fully back would be better.
What is your view and why?

waldopepper42
3rd Jul 2007, 16:16
I was always taught "Let the wind blow the stick" i.e. if the wind is directly behind you it would blow the stick fully forward.

If the wind is from your 4 o'clock, the stick would be at 10 o'clock and so on. (In this case the elevators would be down to keep the tail down, as would the into wind (starboard) aileron to hold the wing wown.


I guess (no personal experience) that one reason for keeping the stick back with the Tiger Moth would be to keep the tail skid firmly in contact with the ground - on the original moth this was the only braking available!

slim_slag
3rd Jul 2007, 16:18
The goal is to keep the tail on the ground. You need to think about what the airflow is doing over the elevator and have the elevator in the correct position for that airflow. The airflow over the elevator comprises propwash and wind. If the tailwind is strong enough you might want to have the stick forward. When you apply power, eg when turning on grass, going over a hill, you might bring the stick back towards neutral, perhaps further.

Tailwheels are most tricky on the ground. There is no hard and fast rule as to where the stick should be, but most of the time it will be back. Can you not feel what is happening?

India Four Two
3rd Jul 2007, 16:21
OK. I'll bite first (alright, make that third - must learn to type faster). I've done a lot of glider towing in high winds on grass fields in Bellanca Scouts.

My club's standard procedure when taxying is to hold the stick in the opposite corner from where the wind is coming from. I've found this becomes a habit even in light winds.

I think the argument about bumps or dips is a red herring. You should never be taxying fast enough to be in a potential nose-over situation.

My test of whether the wind was too strong for a downwind taxy was to see if there was any problem turning out of wind at the end of the landing run. If in doubt, shut down and arrange for help to push back.

Don't underestimate the danger of downwind taxying. My favourite rental 172 was totalled by someone who landed in a 40 kt wind and then tried to backtrack. He was instantly on his back.

Chipmunks in a UAS in the 60s? Surely you mean the 50s?

davidatter708
3rd Jul 2007, 16:28
Some aircraft have to have stick back to engage the stearing in the tail wheel one springs straight to mind a T6 texan havard whatever u want to call the thing

Chilli Monster
3rd Jul 2007, 16:37
Chipmunks in a UAS in the 60s? Surely you mean the 50s? They were still using them in the late 70's! (78 was my one and only UAS chippy flight)

Shaggy Sheep Driver
3rd Jul 2007, 17:03
As some have said, if the tailwind is stronger than the propwash, stick forward. The other way round - stick back. On the Chipmunk it's easy to tell - if the tailwind is stronger it tends to blow the rudder and elevator to the stops and you have to counter that and can easily feel in through the controls. If it's doing that, keep the stick forward. But if you increase power, the propwash may dominate instead, so stick back.

The only time I almost had a Chippy on its nose was in a very strong tailwind on a concrete apron. I was taxying slowly downwind with a couple of notches of brake set for steering purposes. I inadvertantly allowed the wind to catch the rudder, which blew hard over to the left, instanly locking the left main wheel. Despite forward stick the tail came up, but thankfully (and because of forward stick) it came down again as soon as I centralised the rudder.

SSD

India Four Two
3rd Jul 2007, 17:16
They were still using them in the late 70's! (78 was my one and only UAS chippy flight)I must learn to engage my brain before typing - I meant to say Tiger Moth, as Jerico referred to in his first post.

I was lucky enough to get 170 hours and a PFB on Chipmunks in UBAS in the 60s (hence my query) and then a few years ago, I had one flight in a Bulldog at Old Sarum. Nice, but I still prefer the Chippy.

High Wing Drifter
3rd Jul 2007, 17:28
I have occasionally felt the tail going light with just a light tailwind when taxing. I just centralise the stick, that will keep the tail on the floor.

kitfoxman
3rd Jul 2007, 17:42
Let the wind blow the stick is the way i've been taught and practise. If the winds that strong or gusty, stay in the clubhouse.........

shortstripper
3rd Jul 2007, 17:50
I don't quite get the idea of sick in the opposite direction to the wind? or "let the wind blow the stick" ... Perhaps for the elevator, but ailerons would be held "wing down" to the crosswind when there's it's from the front or "wing up" if the crosswind is from behind. Stick forward, back or neutal depends on wind, propwash, type ect ect. I often put in forward stick with a burst of throttle when trying to initiate a turn for instance (to take the weight off the tailwheel/skid). There is no hard and fast rule ... it's just something you end up doing instinctively for whichever type you fly surely?

SS

Islander2
3rd Jul 2007, 17:57
Let the wind blow the stick is the way i've been taught and practise.Nice and simple to remember ... but unfortunately incorrect! That advice would put the stick on the wrong side of the cockpit for a quartering headwind.

18greens
3rd Jul 2007, 18:00
I agree with short stripper. If the wind is quartering from the front you want the stick back but pointing toward the wind to keep that wing down. Was there pehaps another line to 'let the wind blow the stick??'

Plourde used the adage 'Climb into wind, Dive away from the wind' to remember where to put the stick. Whether you put the stick neutral or forward in a tailwind depends on the type. If you fly a pitts they say it doesn't matter where you put the stick.

robin
3rd Jul 2007, 18:21
Having seen the results of a 'stick-back in a tailwind' it reinforced the need to hold the controls in the correct place for the wind and the type, and to use wing and tail walkers if necessary

foxmoth
3rd Jul 2007, 18:59
Having flown a dH82a last week in strong winds (I gave up after 6 flights when it went over 35 kts!) I think I can speak from experience that 'Climb into wind, Dive away from the wind' works - I did also have a wing walker for taxiing in and out and actually ended up doing the changeovers by landing, turning about 10 degrees off to get off the runway then into wind while swapping students, I was also very lucky that the wind was straight down the runway, and unusually, not changing direction during the gusts!:}

kitfoxman
3rd Jul 2007, 21:28
Nice and simple to remember ... but unfortunately incorrect! That advice would put the stick on the wrong side of the cockpit for a quartering headwind

Read the question. Taxing DOWNWIND, thats what i answered, no mention of cross winds. You asked and answered that question!:ok:

shortstripper
4th Jul 2007, 02:44
Shemy,

I've recently done my Gliding Scholarship in the Vigilant with the ATC. Now everyone I flew with told me to keep the control column fully back. To keep the back wheel on the ground. Whatever the wind speed was, as long as it is sensible.

Do that and it's only a matter of time before you tip on your nose! I've only ever flown a Grob 109 once (so it may be that there is a reason for what you've been told), but in principal, because of it's "T" tail being out of the prop wash ... it's even more likely to tip with a tailwind! Following the hard and fast rule of holding the stick back at all times when taxiing a taildragger is pure folly!!!

SS

Shaggy Sheep Driver
4th Jul 2007, 10:08
SS is quite correct. If the wind over the elevator is from trailing edge to leading edge due a strong tailwind on the ground (accentuated in a 'T' tailed taildragger beciase the elevator will not be much affected by propwash), and you keep the stick back, the elevator will develop lift and unless the aeroplane is very tail-heavy the tail will rise.

FlyingForFun
4th Jul 2007, 16:20
Out of interest, why is this thread talking purely about tail-draggers?

Although the resulst of getting it wrong are probably far less serious, exactly the same applies in tricycles - so shouldn't it be taught to all PPLs? Certainly when I used to instruct on C152s I could (and did) demonstrate it quite easilly with a 25-30kt wind, by parking the aircraft pointing downwind, playing around with the elevator, and noting the change in attitude by reference to a distant object. (I don't recommend trying this demonstration in a tail-dragger though!)

FFF
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VH-BOX
5th Jul 2007, 07:52
Hello all, this is my first post from over here in Perth Australia. I have been flying lightly wing-loaded tailwheel aircraft for over 25 years, I currently own a 1946 Piper J3 Cub and a Jodel D11, but have previously owned; another J3 Cub, 2 Stinsons, a Pitts Special S1S, the late John Penny's Sopwith Triplane replica (G-PENY), a Fokker EIII 'Eindekker' replica, a Cessna 140 and 180, 2 luscombes, and a Stolpe SA300, all tailwheel types.

There is one very simple rule when taxiing a 'conventional gear' (tailwheel) a/c that goes back to WW1 i.e. "never let the wind see the underside of the upwind anything". Taxying downwind with the stick back does just that, presents the underside of the elevator to the wind. Further, the wind is pushing the a/c along from behind, and that may mean using brakes to slow down, brakes will put weight forward and apply a lifting moment to the tail, if at that point the wind gets under the elevator you are heading for a prop strike with no hope of recovery. It does happen, I have seen a Stinson 108 suffer a very expensive prop strike taxiing upwind, and it happened so fast you would not believe it. The pilot was a high time airbus captain with very little tailwheel time. These are very different aircraft, the old cliche' that "the flight starts when you open the hanger doors, and doesn't end until you close them again", really is true.