Stick and Rudder and Rudder and Rudder

[AdamZ]

Saturday I had the opportunity to fly with my friend Dave in his Chipmunk. WOW! What a neat plane! The plane pretty much has semetrical wings and as I few it from the back seat all I really had avaialbel to me was the ASI, Altimeter and needle and ball.

First I'll say that it was a hell of a lot of fun. Second, as I sat in the back I kept saying to myself "now I get it!" meaning that the rudder was so damn important in the turns. Yes I understand the whole cordinated turn thing and have since my training but never have I flown a plane that required such affirmative use of the rudder to keep the plane stabilzed. I mean I could really feel it in my ass when I took an uncoordinated turn and stepped on the ball. I've flown 300hp birds where rudder opposite the turn was required but nothing I have ever flow required so much rudder input both in level flight and especially in turns.

So I've been wondering, is this because its a tail dragger, do the semetrical wings have anything to do with it. The engine is not tremendously big only about 145hp. Can anyone give me some guidance here?

 

[tonycondon]

most likely draggy ailerons and an undersized vertical stab

 

[Fearless Tower]

So I've been wondering, is this because its a tail dragger, do the semetrical wings have anything to do with it. The engine is not tremendously big only about 115hp. Can anyone give me some guidance here?

Taildragger has nothing to do with it - it is more a matter of the vintage.

Most modern GA planes that we are used to are designed with differential aileron travel to help reduce the adverse yaw that naturally occurs when you turn an airplane. In other words, the up and down aileron don't equally deflect in most of the planes we fly.

Older types will definitely make you work harder on the rudder.

Try a DC-3....if you don't use the rudder - that airplane will not turn.

 

[RoscoeT]

So I've been wondering, is this because its a tail dragger, do the semetrical wings have anything to do with it. The engine is not tremendously big only about 115hp. Can anyone give me some guidance here?

Cool plane! Early 40's aileron technology + long wings = lots of adverse yaw.

 

[Capt. Geoffrey Thorpe]

Not that familiar with that particular aircraft. But if it was designed with a symmetrical air foil, it also probably has symmetrical aileron deflections so they pretty much work the same upside down as right side up.

"Typical" "modern" aircraft do things like asymmetric aileron deflections (or playing games with the hinging) to un-yaw the behavior when you turn the wheel while right side up. Those would make the airplane adverse yaw even worse if you were flying inverted…

 

[vontresc]

Yep long wings with unbalanced ailerons will give you tons of adverse yaw. Our L-23 Blanik glider is the poster child for adverse yaw. When I give poeple rides, I have them try turning the airplane with the ailerons only. Most trike drivers are suprised that putting in right ailerons makes the nose swing significantly to the left.

 

[dmccormack]

Fun, ain't it?



My first vintage TW flight was in a Taylorcraft L-2. That ball was anywhere but centered and I felt like I was back to square one.

After I bought the Chief, I truly learned how to use rudder. In these vintage airplanes you basically push rudder and then apply aileron (at least it feels that way).

 

[Henning]

Saturday I had the opportunity to fly with my friend Dave in his Chipmunk. WOW! What a neat plane! The plane pretty much has semetrical wings and as I few it from the back seat all I really had avaialbel to me was the ASI, Altimeter and needle and ball.

First I'll say that it was a hell of a lot of fun. Second, as I sat in the back I kept saying to myself "now I get it!" meaning that the rudder was so damn important in the turns. Yes I understand the whole cordinated turn thing and have since my training but never have I flown a plane that required such affirmative use of the rudder to keep the plane stabilzed. I mean I could really feel it in my ass when I took an uncoordinated turn and stepped on the ball. I've flown 300hp birds where rudder opposite the turn was required but nothing I have ever flow required so much rudder input both in level flight and especially in turns.

So I've been wondering, is this because its a tail dragger, do the semetrical wings have anything to do with it. The engine is not tremendously big only about 115hp. Can anyone give me some guidance here?

It's because you sit in the back that you feel it more, that's why back seat passengers throw up more frequently. Also the aerodynamic properties of the airframe aren't as refined and balanced as later model planes.

 

[Dan Thomas]

The engine is not tremendously big only about 115hp.

145 HP. The adverse yaw is typical of "real" airplanes: airplanes that teach a pilot to use all the controls, all the time.

Dan

 

[Henning]

145 HP. The adverse yaw is typical of "real" airplanes: airplanes that teach a pilot to use all the controls, all the time.

Dan

So, to be a "real" airplane requires poor/primitive design work?

 

[PittsDriver]

It's because you sit in the back that you feel it more, that's why back seat passengers throw up more frequently. Also the aerodynamic properties of the airframe aren't as refined and balanced as later model planes.

Airplanes are all a big kludge of engineering compromises and patches to problems the design created. Engines are mounted at an offset angle, vertical stabs are offset a few degrees, rudder work is required to offset all manner of forces that the design of the plane created. I'm not sure I'd say its so much a level of refinement as it is just the nature of the beast. You might say harmonized controls are refined. I might say the opposite is responsive and more honest and leaves me feeling more connected with my hurtling contraption of compromises. But then, maybe that's not as highly valued in some planes so we're probably both right.

 

[Henning]

Airplanes are all a big kludge of engineering compromises and patches to problems the design created. Engines are mounted at an offset angle, vertical stabs are offset a few degrees, rudder work is required to offset all manner of forces that the design of the plane created. I'm not sure I'd say its so much a level of refinement as it is just the nature of the beast. You might say harmonized controls are refined. I might say the opposite is responsive and more honest and leaves me feeling more connected with my hurtling contraption of compromises. But then, maybe that's not as highly valued in some planes so we're probably both right.

Well, that's just it, they are all compromises, all machines are. Not every job has the same requirements out of a machine so we build them to meet the most criteria for that market mission. That's the real advantage to Experimental, you can fine tune your design to meet your specific mission.

 

[dmccormack]

So, to be a "real" airplane requires poor/primitive design work?

Vintage GA airplane design had to balance relatively low HP/Weight powerplants, high lift/ drag airfoils, with relatively inexpensive and simple structures and materials.

Those designs placed more burden on the pilot. Later designs were able to overcome various shortcomings through other compromises.

I don't think that means the design/ engineering then was merely "poor and primitive."

 

[Dan Thomas]

I don't think that means the design/ engineering then was merely "poor and primitive."

The Chipmunk was a military trainer used in Canada and Britain. It trained pilots who would eventually fly fighters. Fighters need to be fast and nimble, and any stuff that makes the airplane easy to fly will also reduce its maneuverability and speed. So the Chipmunk was made to act so that the pilots learned to fly. Really fly. Not drive. Even if the 145-hp Cessna 172 had been available, the air forces wouldn't have used it to train fighter pilots.

http://en.wikipedia.org/wiki/De_Havilland_Canada_DHC-1_Chipmunk

Dan

 

[AdamZ]

145 HP. The adverse yaw is typical of "real" airplanes: airplanes that teach a pilot to use all the controls, all the time.

Dan

That right! I stand corrected on the HP.

 

[David]

It was a lot of fun for me too. I've only had my Dad and son up as passengers. Neither one is a pilot. You're the first pilot that's flown with me in it.

 

[ScottM]

I love the chipmunk. Flew one in Canada once and had a great time.

Here are some pics of my flight.

LOVE the VIS!