OS VF .46 /Pipe on TEDS IMITATION

This is a question for Ted Fancher or Paul Pamposo.

Did either one of you ever put a VF .40 or 46 with a pipe on the
Imitation? If so how much work was it to modify it? Did you need tail weight as the OS VF is heavier that the St .46 that the plane was designed for? Any insight would be appreciated as I am considering doing this. Thank you Walter Hicks

Hi Walter,
FWIW: That 46 was last used for a few flights in a 67 oz. '92 Cardinal based plane of Aaron's. It had absolutely no problems pulling that monster all over the sky with a 3.75 pitch 3 blade Eather. It's probably not quite run in fully, yet. I do believe it would be a but too much for the Imitation. William Davis from here is runnung a K&B 40 (like Les Mc. used to use) to fly his Imitation, and it is plenty.
I do remember David Fitzgerald running a 40VF in a built up plane that I believe was based on the Imitation at the NATS when he was just returning to the event.
Bill <><

P.S. We play the third round game this Friday night against the #1 seed out of the West in our 4A State Playoffs. Won 40-13 last Friday and it could have been worse. We ended up playing a lot of guys that don't get dirty too often for the whole 4th quarter.

>Hi Walter,
>FWIW: That 46 was last used for a few flights in a 67 oz.
>'92 Cardinal based plane of Aaron's. It had absolutely no
>problems pulling that monster all over the sky with a 3.75
>pitch 3 blade Eather. It's probably not quite run in fully,
>yet. I do believe it would be a but too much for the
>Imitation. William Davis from here is runnung a K&B 40
>(like Les Mc. used to use) to fly his Imitation, and it is
>plenty.
>I do remember David Fitzgerald running a 40VF in a built up
>plane that I believe was based on the Imitation at the NATS
>when he was just returning to the event.
>Bill <>< (snip)

Bill, you need to take a tip from "Tim, the tool man, Taylor." You can never have too much power. If a 4-cylinder engine will run your car, why do you want a 6 cylinder engine? Simply for those moments when it comes in handy (like climbing a hill, or when you need to accelerate around another car.) Well, our airplanes do climb hills (sort of, and at quite steep angles, too) and they do need to accelerate out of corners in order to maintain maneuver speed. That extra power or available thrust comes in handy at times.

I feel you can never over power an airplane. You can put too much weight in an airplane from a too large engine, and you can have too much uncontrolled power, and you can sometimes be guilty of not harnessing it properly. So the key is to harness it, control it, and make sure it is not too much weight. Since the original question involved weight and you said Dave put a 40 VF on a similar plane, he has already probably answered that question. It would really depend on your building skills in keeping the weight down and the plane properly balanced.

Your mentioned the use of a 46 in a 67 ounce Cardinal. Matt's current ship weighs considerably less, is (I think) smaller in size, and has a PA 65 on it with a 13 3/4 three blade prop. Is it too much power? Well, since he wants to get a 76 and put it in the same size plane, I guess he doesn't think so. In fact he was even thinking of reducing the size by about 40 square inches.

Interestingly enough, you can usually carry a little more weight when you have a little more power. We demonstrated that amply by putting a 53 in a 35 size plane. This was a smaller size plane that had grown a bit over weight through a refinish job. But adding the 53 (with its extra weight of 2 more ounces) brought it back to life.

My take on the situation, if you want to try it, go for it. Look at what Al Rabe is putting in his Snaggletooth these days. Matt has built a classic Rabe Musting like Al originally powered with a ST 46. It will have either a PA 61 or 65 for power. Put a 4-blade prop on it for looks. Yeah, that's more like it.

>>Hi Walter,
>>FWIW: That 46 was last used for a few flights in a 67 oz.
>>'92 Cardinal based plane of Aaron's. It had absolutely no
>>problems pulling that monster all over the sky with a 3.75
>>pitch 3 blade Eather. It's probably not quite run in fully,
>>yet. I do believe it would be a but too much for the
>>Imitation. William Davis from here is runnung a K&B 40
>>(like Les Mc. used to use) to fly his Imitation, and it is
>>plenty.
>>I do remember David Fitzgerald running a 40VF in a built up
>>plane that I believe was based on the Imitation at the NATS
>>when he was just returning to the event.
>>Bill <>< (snip)
>
>Bill, you need to take a tip from "Tim, the tool man,
>Taylor." You can never have too much power. If a
>4-cylinder engine will run your car, why do you want a 6
>cylinder engine? Simply for those moments when it comes in
>handy (like climbing a hill, or when you need to accelerate
>around another car.) Well, our airplanes do climb hills
>(sort of, and at quite steep angles, too) and they do need
>to accelerate out of corners in order to maintain maneuver
>speed. That extra power or available thrust comes in handy
>at times.

No arument here on more "power" and it's benefit.

>I feel you can never over power an airplane. You can put
>too much weight in an airplane from a too large engine, and
>you can have too much uncontrolled power, and you can
>sometimes be guilty of not harnessing it properly. So the
>key is to harness it, control it, and make sure it is not
>too much weight. Since the original question involved
>weight and you said Dave put a 40 VF on a similar plane, he
>has already probably answered that question. It would
>really depend on your building skills in keeping the weight
>down and the plane properly balanced.

For one, Dave's plane was built up, the Imitation is not, a profile is harder to keep light. The VF's are by no means light, especially the whole set up with pipe. This would have a double negative effect on wing loading.

>Your mentioned the use of a 46 in a 67 ounce Cardinal.
>Matt's current ship weighs considerably less, is (I think)
>smaller in size, and has a PA 65 on it with a 13 3/4 three
>blade prop. Is it too much power? Well, since he wants to
>get a 76 and put it in the same size plane, I guess he
>doesn't think so. In fact he was even thinking of reducing
>the size by about 40 square inches.

I went from a 40 to a 51 in my curernt PAMPA ship, and will probably go to a 61 if I have to fly it this year. Saturn size, 54 oz. RTF

>Interestingly enough, you can usually carry a little more
>weight when you have a little more power. We demonstrated
>that amply by putting a 53 in a 35 size plane. This was a
>smaller size plane that had grown a bit over weight through
>a refinish job. But adding the 53 (with its extra weight of
>2 more ounces) brought it back to life.
>
>My take on the situation, if you want to try it, go for it.
>Look at what Al Rabe is putting in his Snaggletooth these
>days. Matt has built a classic Rabe Musting like Al
>originally powered with a ST 46. It will have either a PA
>61 or 65 for power. Put a 4-blade prop on it for looks.
>Yeah, that's more like it.

Yes, and Al is planning on using a .77 in Snaggletooth which you know has a PA 65 in it already. I use a ST 46 in my Spacehound, a 35 size plane.

Walter bought a 46VF from Aaron recently. I do know the engine's history. It is very strong ans a hirh rpm engine.
Not knowing how much time and experience Walter has (I do know he is also a football coach which means he isn't filled up with spare time), the scenario of making all the variables work in a VF 46 pipe set up on a "small", to a degree, airplane might be very frustrating.I don't know if he is aware of the ways to harness the power. I do know that the Imitation doesn't need that much engine to really fly well so I suggested something that I feel would give the pilot more air time.
Bill <><

Hi Bill, what kind of pipe is with the Vf I purchased and what was the pipe length ? Thanks W Hicks

The pipe is a Smith/Werwage 40-46 size. I believe the pipe was set at 17 1/2, but I would have to ask Aaron or Randy.
Bill <><

>This is a question for Ted Fancher or Paul Pamposo.
>
> Did either one of you ever put a VF .40 or 46 with a
>pipe on the
>Imitation? If so how much work was it to modify it? Did you
>need tail weight as the OS VF is heavier that the St .46
>that the plane was designed for? Any insight would be
>appreciated as I am considering doing this.

RUN, do not walk, to the shop to perform this mod. I don't know if Paul is monitoring the forum, but he had two Imitiations done this way, and they both worked well. The weight increase is EASILY handled by the Imitation wing, and the superior *performance* (not power). And my Imitation XL is a full-fuse version with a wing cut straight from the plans - and it has flown with a 40VF, 46VF, PA40, and a PA61, and managed to qualify at the NATs 6 different times.

I'm not going to flog this dead horse again - you *can* have too much power, as any power in excess of what it requires results in excess speed. Physics does not care about the odd notions stunt fliers hold of what 'power' means.

>(snip) I'm not going to flog this dead horse again - you *can*
>have too much power, as any power in excess of what it
>requires results in excess speed. Physics does not care
>about the odd notions stunt fliers hold of what 'power'
>means.
>
> Brett

Is there a term that we can agree on here, Brett, because I don't like to leave on the note that extra power always equates in extra speed. Maybe we are just using different terms or not utilizing it properly.

I know what you are saying and we totally agree on these things so I am just trying to find an agreement of terms, and not in any way debate a point as if there is some difference of opinion here.

First off, we don't run our airplane engines at full speed, so sometimes we can just dial them down a bit (just like with our car, we don't push the pedal to the metal while driving down the highway--unless we want to pass quickly, climb a hill, whatever. Maybe in this sense the term "available power" would be better.

On the same vein, my Buick loafs at about 1500 rpm while cruising 65 on the Interstate. It is probably not developing a lot of power in that configuration. It has a lot of available power, or power potential in that big engine. Still, I am not driving any faster than any other (and usually getting passed by most people).

On the other hand, if I geared it down from 4th speed overdrive and went down to first gear, it would probably be over the redline of 5500 rpm (Never tried it, and don't plan to) trying to maintain the highway speed limit. But, at the same time, even though the car isn't moving any faster, I am sure the engine would be cranking out much more "power" (is that the correct term, or is there a better one for me to use) while in first gear and reving up to its limit.

This is the principle we need to impress upon people, that the larger engine does not necessarily mean more speed. We just need to gear it differently, slow it down a bit, or whatever, just as you were able to do while using a 40 VF, 46 VF and even PA 61 in the same plane.

LAST EDITED ON Nov-22-04 AT 11:34 AM (CST)
 
Here I go again, seconding Brett.

Really, guys, it's only because he always seems to get here first.

Let me approach it just a little differently.

I flew my original Imitation more than any airplane I've ever had, thousands of flights. After I was done with it I gave it to Paul who literally wore it out with who knows how many hundred more. It was a delightful and easy to fly airplane. Many airplanes similar to David Fitz' built up version will built here in California. The comments were without exception positive.

I think the Imitation's greatest asset was the way it could shrug its shoulders at trim changes. My airplane was flown with a number of different engines, different CGs, and with and without a bunch of weight at each end to balance particularly heavy or light engines. It simply didn't seem to care.

One of the more interesting applications was the last form in which I flew it with the Enya .46 four stroke. Because of the rear intake this "heaviest of the engines ever installed" had to be mounted further forward than I would have ever designed for such a mass. The result was the need for a bunch of lead in the tail. This was a gross example of the dreaded "barbell" effect discussed in stunt ever since Bob Gialdini's great Olympic article brought the weight room into the stunt equation.

In this configuration the ship ended up weighing around 62oz as I recall and this was on only 620 or so square inches. It flew great and was the configuration in which I ultimately took it out for hundreds of flight just for fun. I enjoyed it more in this state than any of the dozens of other set-ups.

Having said that, I'm not suggesting that the barbell effect was advantageous, only that the powertrain embraced the effect and minimized it. Another way of saying the right sort of power (as opposed to simply "more" of it) can overcome lots of problems that a less malleable power train might not.

The bottom line is that the piped .46 would only produce a similar situation but with less of the added mass on the extremes. The piped OS operates in a very similar power delivery state as the four stroke...consistent one speed operation...but with the slight advantage of a little boost going uphill which is, of course, a shortcoming of the one speed four banger.

Having spoken way too many words which are only repetitive to other posts...GO FOR IT!

Ted

Oops, I should point out the "Paul" to whom I gave the original Imitation is not Paul Walker but Paul Pomposo, a local young expert flyer. I know Paul W. would have profited greatly in his quest for stunt superstardom had he had access to the Imitation but, unfortunately he's had to struggle along on his own. Too bad, huh?

Just a few weeks ago Paul Pomposo loaned me his Imitation/40VF for a day or two of flying.

Though Paul claims to have built a zillion (6?) Imitations, that particular airframe suffered from fuse-flex and all of the inherent handling ills.

While the airframe was a dissapointment, the powertrain was a revelation to this non-pipe flyer. His package has a beautifull pipe motor run, power everywhere and one flip starts. In fact, the engine/pipe combo made what would probably have been a complete dog, if powered with an ST-46, into a very very flyable plane.

The NEXT DAY I went out and got myself a 40VF for my next project.

The Imitation sure wouldnt NEED 46 power (The 40VF is amazing!) but if Ted says it'll work I'd be willing to do it!

Paul stays away from the internet slugfests but you can find him in the PAMPA directory. I'm sure he'd be happy to share his setup with you.

BIGS

" What constitutes the dignity of a craft is that it creates a fellowship, that it binds men together and fashions for them a common language. For there is but one problem - the problem of human relations."

>Just a few weeks ago Paul Pomposo loaned me his
>Imitation/40VF for a day or two of flying.
>
>Though Paul claims to have built a zillion (6?) Imitations,
>that particular airframe suffered from fuse-flex and all of
>the inherent handling ills.
>
>While the airframe was a dissapointment, the powertrain was
>a revelation to this non-pipe flyer. His package has a
>beautifull pipe motor run, power everywhere and one flip
>starts. In fact, the engine/pipe combo made what would
>probably have been a complete dog, if powered with an ST-46,
>into a very very flyable plane.
>
>The NEXT DAY I went out and got myself a 40VF for my next
>project.
>
>The Imitation sure wouldnt NEED 46 power (The 40VF is
>amazing!) but if Ted says it'll work I'd be willing to do
>it!
>
>Paul stays away from the internet slugfests but you can find
>him in the PAMPA directory. I'm sure he'd be happy to share
>his setup with you.
>
>BIGS

Well I rarely spend time on the forum, but this is an excuse for me to change my habbits.

Walter, I built 5 Imitations in the past and had absolute success with the 40VF on this. The only modification that I recall was I had to lower the engine mount .25" to allow some clearance for the 1.25" header. I never really noticed much of a change in the CG going from a ST. 46 to the VF. Mine was somewhat tail heavy, so it worked out for the better.

Let me know how this system seems to work for you

>Just a few weeks ago Paul Pomposo loaned me his
>Imitation/40VF for a day or two of flying.
>
>Though Paul claims to have built a zillion (6?) Imitations,
>that particular airframe suffered from fuse-flex and all of
>the inherent handling ills.
>
>While the airframe was a dissapointment, the powertrain was
>a revelation to this non-pipe flyer. His package has a
>beautifull pipe motor run, power everywhere and one flip
>starts. In fact, the engine/pipe combo made what would
>probably have been a complete dog, if powered with an ST-46,
>into a very very flyable plane.
>
>The NEXT DAY I went out and got myself a 40VF for my next
>project.
>
>The Imitation sure wouldnt NEED 46 power (The 40VF is
>amazing!) but if Ted says it'll work I'd be willing to do
>it!

I would point out that the same engine, straight out of the box, did manage to pull around some fairly decent 700 square inch, 65 oz airplanes. To the tune of 7 NATs wins. You might - and I emphasize might - be able to get better performance from some other engine. But I have yet to find one that's a lot better, and I am pretty darn picky.

n this configuration the ship ended up weighing around 62oz
>as I recall and this was on only 620 or so square inches.
>It flew great and was the configuration in which I
>ultimately took it out for hundreds of flight just for fun.
>I enjoyed it more in this state than any of the dozens of
>other set-ups.

Mine flew just fine at 64 oz and 610 square inches (different wing tips). In Lubbock. In 104 degrees. In a 15 mph wind.

LAST EDITED ON Nov-22-04 AT 04:44 PM (CST)
 
Brett,

Man, do I hope that's true. My new 620 inch plane (Sortatation wing) looks to be coming out about 58oz. Darned foam wings . Piped 40 for power.

Thanks you Ted ,Bret and others. The plane I will be using is my discuised Imitation (looks like a Chipmunk ) complete with a cowl and wheelpants. It flies very well with LA .46 no problems. I have been flying the BIG Lazer 200 with Saito .72 wonderful plane but not at all practical.(try flying an 84 oz plane in the wind!) However the Imitation will fly in anything,fast /slow/whatever. Once a contest at Woodland Hills was over because no one wanted to fly in the wind and for fun I flew the pattern with the Imitation and LA .46.
For whatever reasons the Saito ran well for over a year and then has been a pain. I have been told the VF .46 and pipe are flip and fly.
3 of us in our area will be using this como this year. The Imitation is probably about 58 oz now so weight is not the issue with this design. Thanks to all of you I will be using the old dremel tonight!
(by the way I am an advanced flier relatively unknown and low and behold the experts are always there to help ) some may want to do there homework before making comments about these folks.By the way Caron fiber mat does wonders for the flexing of the rear fuse and tail on the Imitation mine does very little!Thanks again everyone.

>Thanks you Ted ,Bret and others. The plane I will be using
>is my discuised Imitation (looks like a Chipmunk ) complete
>with a cowl and wheelpants. It flies very well with LA .46
>no problems. I have been flying the BIG Lazer 200 with Saito
>.72 wonderful plane but not at all practical.(try flying an
>84 oz plane in the wind!) However the Imitation will fly in
>anything,fast /slow/whatever. Once a contest at Woodland
>Hills was over because no one wanted to fly in the wind and
>for fun I flew the pattern with the Imitation and LA .46.
>For whatever reasons the Saito ran well for over a year and
>then has been a pain. I have been told the VF .46 and pipe
>are flip and fly.
>3 of us in our area will be using this como this year. The
>Imitation is probably about 58 oz now so weight is not the
>issue with this design. Thanks to all of you I will be using
>the old dremel tonight!
>(by the way I am an advanced flier relatively unknown and
>low and behold the experts are always there to help ) some
>may want to do there homework before making comments about
>these folks.By the way Caron fiber mat does wonders for the
>flexing of the rear fuse and tail on the Imitation mine does
>very little!Thanks again everyone.

You're welcome, Walter.

Seems like Imatation derivatives used to grow like corn in Iowa out your way. There ought to be a couple of dozen just collecting dust somewhere! Good luck.

Big Seminole makes a good point about the aft fuse on the Imitation. It is long and hangs on to a big tail and it is prone to flex. Another good method of controlling that is to lay in a couple of strips of 1/2" X .014 carbon strips above and below the wing. Either build the fuse in "top", "middle" and "bottom" chunks with the carbon layed in (flat) or before the fuse is cut out of the sheet, run it through a band saw top and bottom and insert the carbon.