Prewar vs postwar flying charecteristics

[likeTs2]

Hello all,

I just got my tail wheel endorsement in a 1940 BL65. I really like flying the taylorcraft. I recently got a glider rating and enjoy the similarities in control response.

I have noticed that the rudder in the prewar models is larger than the postwar models. What differences in flight charecteristics does this create. I had my instructor show me how to do spin recoveries, and I was wondering if the rudder size affected recovery techniques.

Thanks

[Hank Jarrett]

Re: Prewar vs postwar flying charecteristics

Rudder on pre wars is more effective. About the only place you will notice much (before you have a BUNCH of hours in both) is doing a really steep slip. The pre war planes run out of aileron first (put the wheel hard over and you can modulate the rudder in the end of it's travel) and the post wars run out of rudder (rudder hard over and you can move the very edge of the wheel motion). It isn't a huge difference since either will have the guy in the right seat grabbing the windshield tubes. ;-)

I LOVE steep slips!

Hank

[3Dreaming]

Re: Prewar vs postwar flying charecteristics

Like Hank said the pre war slips nicer. The rudders are actually about the same size area wise. The pre war is short and long, while the post war is taller and more narrow. the bigger difference is in the vertical fin. The vertical fin on the pre war is smaller. Post war they made the vertical fin about 4 inches taller and carried the 4 inches all the way down the leading edge. They did this for increased directional stability.

Personally I like the pre war better, but that is based on the fact that have about 100 times the hours in prewar compared to post war. Honestly they both fly nice.

[lfries]

Re: Prewar vs postwar flying charecteristics

I was doing a check out in a pre war. After watching basically no use of the trim I made a comment about lightning up control pressure. He gave me the airplane and I was amazed at the lack of need to adjust the trim.

[3Dreaming]

Re: Prewar vs postwar flying charecteristics

I was doing a check out in a pre war. After watching basically no use of the trim I made a comment about lightning up control pressure. He gave me the airplane and I was amazed at the lack of need to adjust the trim.

I think that is more a function of the CG rather than pre war post war thing. The trim system on the pre war airplanes are also quite inadequate compared to post war. You go from no trim on the A model, to the flipper trim, to the small tab in the elevator on the pre war airplanes. They just don't compare to the big trim tab on the post war airplanes.

[likeTs2]

Re: Prewar vs postwar flying charecteristics

Thank you all for the replies. I have also noticed that the prewar models are about 50 to 100 lbs. lighter that's the post war according to the specs. I assume that is due to a more delux interior. Are the brakes on the post war models any better. Standing on the brake pedals I can barely keep the the plane from moving during a run up for a mag and carb heat check.

I will be looking for a plane sometime after the first of the year. It does not seem that there is enough difference in the post and pre war planes to make that much of a difference as long as the overall condition is good. My only problem is that there seems to be a lot better selection on the Eastern Seaboard and the Deep South.

[3Dreaming]

Re: Prewar vs postwar flying charecteristics

Brakes will be the same for both, and they can be adjusted to hold better. There is the weight difference, but there is also a gross weight difference. Pre war airplanes can have a gross weight of 1100, 1150, or 1200 pounds. Post war will be 1200 or more. The thing to look for is useful load. The 1941 BL65 I restored had a useful load of just over 450 pounds, which is pretty good.

[Hank Jarrett]

Re: Prewar vs postwar flying charecteristics

Lighter is better! Many pre war planes have gained weight (some a LOT of weight) over the years. A well done rebuild will take a lot of that weight back out. I think a lot of what Tom Baker (3Dreaming) says is probably correct. When I remember how my pre war performed and handled when I first got her I need to remember that I found out later that the CG and empty weight were NOWHERE NEAR where the paperwork said they were. Any plane you buy you should WEIGH and RECALCULATE the CG! I found out that with a couple of gallons of fuel in the nose and two people my CG was right at the aft limit, NOT where the paperwork said. A little junk in the baggage compartment and we would have been AFT of limit. Might well have been why it felt so "crisp" on the controls and slipped with so much rudder authority! Sure does handle nice with aft CG, but I DO NOT suggest you do it! I shudder to think what could have happened if we had done some spins!

Hank

[flyguy]

Re: Prewar vs postwar flying charecteristics

LikeTs2,
Sent a pvt msg to you.
DC

[astjp2]

Re: Prewar vs postwar flying charecteristics

But they fly faster that way!

Lighter is better! Many pre war planes have gained weight (some a LOT of weight) over the years. A well done rebuild will take a lot of that weight back out. I think a lot of what Tom Baker (3Dreaming) says is probably correct. When I remember how my pre war performed and handled when I first got her I need to remember that I found out later that the CG and empty weight were NOWHERE NEAR where the paperwork said they were. Any plane you buy you should WEIGH and RECALCULATE the CG! I found out that with a couple of gallons of fuel in the nose and two people my CG was right at the aft limit, NOT where the paperwork said. A little junk in the baggage compartment and we would have been AFT of limit. Might well have been why it felt so "crisp" on the controls and slipped with so much rudder authority! Sure does handle nice with aft CG, but I DO NOT suggest you do it! I shudder to think what could have happened if we had done some spins!

Hank

[Hank Jarrett]

Re: Prewar vs postwar flying charecteristics

Yea, in theory (and some actual test experience) they can fly faster with aft CG due to lower tail surface induced drag and less wing induced drag due to less requirement to offset stab down load, BUT it also can kill you faster at low speeds and high AOA! Sometimes MUCH faster!
The B-58 was MUCH faster with aft CG and supersonic. They could pump fuel to an aft tank to reduce stab down force over Mach 1. Trim drag with forward CG really dragged them down and also burned up much more fuel, but if you lost an engine supersonic the plane would decelerate to sub sonic faster than you could pump fuel forward (or dump it) and the plane would loose control. You couldn't fly the Hustler supersonic in the long range fuel configuration in peace time.

Hank

[3Dreaming]

Re: Prewar vs postwar flying charecteristics

On the pre war taking less trim, it might also have to do with the angle of incidence. If you look at many pre war airplanes the trailing edge of the wing is even with the top longeron. On many post war airplane the trailing edge is at least 1 inch or more lower.

[likeTs2]

Re: Prewar vs postwar flying charecteristics

On the subject of trim, the guy who has the BL65 I got my endorsement showed me the little Tim paddles below the stabilizer and told me they were not effective enough to bother with. I never missed not having the trim at all as the control forces are so light.

[LostnSpace]

Re: Prewar vs postwar flying charecteristics

The B-58 was MUCH faster with aft CG and supersonic. They could pump fuel to an aft tank to reduce stab down force over Mach 1. Trim drag with forward CG really dragged them down and also burned up much more fuel, but if you lost an engine supersonic the plane would decelerate to sub sonic faster than you could pump fuel forward (or dump it) and the plane would loose control.

speaking of B-58's, do you know the reason for the one that crashed in Great Salt Lake with a bomb onboard, just remembering from long ago, gary

Hank[/QUOTE]

[Hank Jarrett]

Re: Prewar vs postwar flying charecteristics

I know it was in late April with either one or two casualties (at least one survivor) but I think it was a civilian crew of test personnel from the factory. LOOONG time ago so I certainly don't remember details. My father was with SAC back then, but the Omaha newspapers told us a lot more than my dad ever could. Of course we all know that newspapers are a great source of accurate information. ;-)

Hank