skylarkmk1

Anthony,

I believe you are correct, I will not be able to check until the weekend 17-18 May.

WacoNut

Thanks John,
I will go with 2" to me it looks right and I will not be showing the plane so it's good enogh for me, and I don't want to wait that long[)]. IF I do it right you will barely be able to see them anyhow.
Later!!
Anthony

Stickbuilder

John,

The fairings on the tail have me drooling. I talked to Darrell (Sierra Giant Scale)again this morning. He has promised to get a set of the gear out quickly. He said that the hold-up is due to so many people bending the gear on their airplanes and he is having to repair them. I'm waiting.

Bill, AMA 4720
WACO Brotherhood #1

Hughes500E

My Feedback: (16)

Hey guys,
First flight of the season last night with the Waco I thought I would share!

I did make a few changes over the winter, new under carriage, new aileron servos and Receiver etc etc. It was like maiden flying all over again

Once again the engine right thrust or lack of played into it rudder has a lot of trim. Offset that engine or vertical fin if you're building!
I went from a 16x8 prop to an 18x6 prop and the air frame didn't like it, lots of P factor. I thought I would throw that in for you guys considering gas.
The grand slam, after the third flight I decided to dial in some aileron differential. Not sure if we have talked about this on this thread yet but it is a must. I went for 50% down compared to up on both sides and it's a different aircraft. Flies like a big kite now, even the landing was easier )

skylarkmk1

Bill,

Terry is quite the craftsman, careful and meticulous. While I was there taking the above photos (and more), he was triming the wheel pants to fit around the new landing gear fairings. Test fit, mark, cut, refit, remark and cut. I don't know if he personnally made the gear, tail and cowl fairings, but from watching him work, I would suspect he did.

khodges

My Feedback: (1)

Not that I could find. Consolidated had a factory in San Diego, and another in Ft. Worth. Douglas built them in Tulsa, North American built them in Dallas. Ford had the largest plant,"Greenfield", at Willow Run near Detroit. At the time of completion, it was the largest assembly line in the world, for any product, and the Ford plant turned out over 450 B-24's a month.
The Liberator still holds the record for the most-produced airplane ever.

Waco wanted to build them, but couldn't figure out how to get the wheel pants to retract into the wells

Stickbuilder

We have talked about aileron differential several times. Personally, I use 30% down, as compared to up, and the lack of adverse yaw is just great.

What kind of RPM's are you getting out of your G-26 with the 18X6, and which prop were you using? I really need to know this, since this is the engine that I'm running on the new one.

Once again, I don't advocate any right or down thrust on any R/C model. I build mine straight up at zero/zero. That's what the rudder is for. Every Waco that I've ever flown used throttle management to change altitude, and the elevator controlled speed. I just think that these models look wierd with the prop hanging slunchwise out of the cowl. That's just my opinion, and it's served me well. Using the rudder all the time makes me a better flyer.

Bill, AMA 4720
WACO Brotherhood #1

Stickbuilder

Okay, Here is the roster to date.

WACO BROTHERHOOD MEMBERSHIP:

#1 stickbuilder
#2 Hughes500
#3 Jim Henley
#4 mmattockx
#5 CTflyboy
#6 michaelj2k
#7 Ronj10
#8 gwulle
#9 jim schroer
#10 Skinny Bob
#11 Bart5495
#12 Pimmnz
#13 HarryJ
No. 14 Old Git
#15 ChrisMH
#16 Nerevar
#17 Ricatic
#18 Clay H.
#19 Tripp2Loo
#20 KHodges
#21 Bill Hogue (WACO One)
#22 Mangolo (Waldo)
#23 av8ter
#24 yel914 (Rick)
#25 damifino
#26 skylarkmk1
#27 Jacque
#28 Edwin
#29 AROPLANE
#30 CubNut (Anthony)
#31 BQuartucy (Bob Q)
#32 AERORON
#33 funkymusic
#34 Live Wire (Larry)
#35 obo (Bob)
#36 Jackk36 (Jack)
#37 fatherrooster (Jim)
#38 Ilikebipes
#39 Kestrel0222
#40 CROWMAN17 (Marc)
#41 redcesar
#42 S. Christensen (Scott)
#43 Bill Deidrich
#44 Mike Barbee
#45 mrdhud (Dan Hudson)
#46 SoCalSal
#47 Todd (NightStalker)
#48 argon (Bob Gonzalez)
#49 mango 12 (Scott)
#50 skyjet 1
#51 ZIG
#52 Didg
#53 MarvinE255 (DOC)
#54 Joe Norris (Full Scale WACO Pilot)
#55 vasek
#56 SuperCub Man (Jim)
#57 Black Drape (Ron)
#58 aminiet (Angel Minet)
#59 Snowball
#60 doc zinger
#61 jagnweiner (Scott)
#62 Meesh (Bob)
#63 BigBoy99 (Bernie)
#64 stifts (Steve)
#65 RCWalker (Wallace)
#66 Mobyal
#67 lazyace
#68 bladerunner1955 (Don)
#69 trlambsr
#70 Big Bird (Ken)
#71 Tony V (Tony)
#72 red 1
#73 412t1 (Sean)
#74 Mr Lucky (Ben Warner)
#75 RICKSTUBBZ (Rick Stubblefield)
#76 ffdg (Fred)
#77 tomcraig
#78 Michou41a Michel
#79 Watzscale (Dick Watz)
#80 Devens
#81 msilvestro (Mark)
#82 Cheechukranch (Lewis)
#83 kruzin55 (Chris)
#84 lynchr (Ron)
#85 airplanegeek
#86 Mainer Jim
#87 Garthwood (Charles)
#88 RCBOATMANIAC (Dave)
#89 Thomas B
#90 George Werber
#91 frequent flyer (Don)
#92 adamiani Axex
#93 Kvlasblom
#94 geertdewit (Geert)
#95 Wobble Wing (Bud Halverson)
#96 Joe Gulik
#97 T.L.A.R.eng
#100 nine o nine (Mitch Epstein)



WACO Sisterhood Roster:

S-1 Janelle (Lady Stickbuilder)
S-2 Sissy Nightstalker
S-3 Barb Barbee
S-4 LadyMango (Lynda)
S-5 BUMBLE GEE BEE (Gabi)
S-6 Sue Watz

Bill, AMA 4720
WACO Brotherhood #1

Hughes500E

My Feedback: (16)

I agree, rudder is good I always use it as well but, I'd rather not fly around holding it over either )
No gas here, still running the 3 cylinder, just thought I'd share my find. 18-6 was spinning just over 7800

Stickbuilder

The G-26 spinning a modified Zinger 18X6 has managed to turn almost 7900 rpm so far. It doesn't have much run time on it though. I doubt if I will ever approach those engine speeds on the plane.

Bill, AMA 4720
WACO Brotherhood #1

RICKSTUBBZ

I would like to share my point of view on engine thrust in Radio Control Airplanes. With many radio control airplanes you can get away with no thrust built into the engine mounting. However when you start dealing with an aircraft that has high lift or high drag factors all bets are off.

I agree that learning to fly with the rudder is of most importance in a quest to become a better pilot. Additionally, I would like to respectfully say, learning to properly trim an aircraft is just as important to be a better pilot and a better builder.

Where I fly we get many days with little to no wind in the summer time. And this is where you can easily see a thrust problem show up.

If you have no right thrust built in to an RC plane that needs it, you can trim the rudder to make the airplane fly a strait line from point “A� to point “B� but in doing so the tail is hanging out the left side (crabbing).

Then to get technical, one could go into the fact that now you have to trim left with ailerons to counter the roll coupling created by the right rudder that you are flying with. And if your airplane couples pitch (attitude /elevator) with the rudder, now you have to add elevator trim to compensate for that. All the while a little right thrust could have eliminated all of this.

It is just a matter of preference. With out a doubt even as little as 1° of thrust is a very noticeable difference on a 10� cowl. Personally I prefer to try hiding a skewed propeller so that I can have an airplane that flys strait.

WacoNut

It is all a matter of preference.
I started taking flying lessons in a full scale J-3 about 10 years ago and only logged 4 hours(long story) It made me a much better R/C pilot, I learned alot about trimming an aircraft and speed/energy management. The J-3 was a joy to fly and very easy, trim the plane up for level flight at 1800 RPM's and approx 65mph and if you wanted to climb add throttle when you wanted to decend reduce the throttle, the whole time the plane would maintain the 65mph that you trimmed it for. If you set your R/C plane up to fly at a nominal cruise speed at a given RPM it should climb with power and loose altitude with reduction in power. Once you get the hang of this and learn at what altitude to enter the pattern and at what throttle settings it will make you a much better pilot. To me it is all about speed management.
Anthony

Thomas B

My Feedback: (4)

And yet a goodly number of full scale aircraft do indeed have some right thrust built in, to minimize torque/P-factor/spiral propwash effects.

Yes, you do use trim and airmanship to get the final results you need, but aircraft often have some sort of compensation built in to help reduce pilot workload.

Look at a Cessna Caravan sometime..it has a remarkable amount of right thrust and down thrust built in. A considerable number of single engine aircraft have some right thrust built in. and, there are other compensation fixess as well.

Lots of full size aircraft do thrust line for pitch effects as well. A J-3 has no down thrust, but its big brother, the Pa-11 Super Cub has 4 degrees of downthrust built in.

Look at a side view of a Lake Amphibian sometime....massive upline thrust to counteract the high thrust line.

The modern line of RV experimental aircraft have right thrust built into the motor mount.

Older aircraft, such as the Aeronca Champ, often have the vertical fin offset to help with torque/-factor/spiral propwash. In fact, an article on the Waco club (full scale) website reccomends 1 to 4 degrees of fin offset to help with torque/P-factor/spriral prop wash effects:

http://www.americanwacoclub.com/news...g_v1n3v1n4.htm

Lower powered full scale aircraft typically have the least compensation of these effects, while higher powered aircraft have a bit more.

Finally, some aircraft are rigged with one wing having a tiny incidence difference to the other wing to help with torque/P-factor/spiral prop wash.

Personally, I find it completely acceptable to do some thrust line adjustments on scale models to help minimize trim changes and needed pilot inputs.

Stickbuilder

Not to be argumentative, but none of the airplanes that you mentioned were being built (or even conceived ) when the YMF was built in 1934. The Jacobs 225 can hardly be considered as a high performance engine.

Once again, what do you do when you have the offset engine thrust adjusted for cruise, and then change to a different throttle setting? Back to using the rudder and elevator. Right?

My YMF has an in-flight adjustable horizontal stabilizer (as did the full scale). The full scale had a ground adjustable trim tab for the rudder. You control your up lines and torque reaction during the take off roll with the rudder.

Engine thrust lines and propellor mis-alignment is noted during the static judging at Top Gun as well.

Bill AMA 4720
WACO Brotherhood #1

khodges

My Feedback: (1)

When I "un-arfed" my UMF, I took all the right thrust out by using longer standoffs on one side of the mount. With the G-26 and an 18-6 MA Classic prop, there is a noticable torque reaction any time you "pour the coal" to it, either on take-off or while in the air. Application of right rudder is sufficient to control the tail on takeoff, and right rudder plus a little right aileron will compensate while in the air, unless your airspeed is close to stall, in which case it will try to snap roll to the left. Modulating the throttle by smooth "roll-on" rather than "jamming" it is the key at lower airspeeds, and a safe take-off means letting it build plenty of speed and fly itself off.

Mine also does tend to "crab" a little while in straight and level at cruise, however, I find myself using only a click or so of right rudder trim to straighten it out, with no aileron compensation. I believe it doesn't require aileron input because, the torque reaction to the left would also induce a roll couple to the left (it does, if left uncorrected) and the right rudder trim induces a roll couple to the opposite (right) side, cancelling the coupling tendency. I haven't noticed any elevator trim compensations needed, except the intitial trim for the desired airspeed. My plane is heavier than most of yours, I believe (unless you use a lead-based glue, like I apparently did) so my flying speed and approach speed is likely a bit faster than yours also. I cruise at about 2/3 throttle, descending approach is about 1/2 throttle, and short final is about 1/4 or a bit more, depending on whether it is still air or into the wind (forget downwind landing with this anvil.....er, plane) At any rate, I like how mine flies, at cruise speed the surfaces have plenty of authority, and I have twice the "up" as "down" in my aileron differential. The elevator is especially effective, and I use about 50% expo to try and "dull the edge" to make it less sensitive.

When at CCA last year, John and I noted that there were several UPF-7's with an offset V-stab, and asked about it. The answer I remember was that they were probably changed during restoration, or may have been an assembly line mod late in the series. John, have you learned any more about this?

nine o nine

My Feedback: (1)

Having been a "pattern" pilot (as well as a full scale flight instructor...my AMA # is CFII) for a number of years before getting into scale I always use whatever is available for trimming an airplane. I derived right and downthrust amounts through flight testing for straight uplines and consistent pitch while changing speeds. Todays cpmputer radios allow mixing to compensate for all throttle changes as well as lack of offset. The flip flop planes are usually set up as zero zero so up or downthrust isn't necessary although a touch of elevator is sometimes mixed in at low throttle to hold a pure veritcal downline.
Also elevator and aileron compensation is often used with knife edge rudder application to cancel roll and pitch coupling. Having said all this and I realize most of you know all this anyway, our Waco bipes have lifting angle of incidence built in and lifting wing sections so they're all sensitive to speed changes. The old throttle controls altitude and pitch controls speed. By careful mixing of controls, either in the xmtr, or with your thumbs, most unwanted flightpath traits can be worked out. The need for engine offset is sometimes necessary, I feel, if the plane is significantly overpowerd though. As far as aileron differential goes, 2 up to 1 down is a good guestimate to start with. Again, a computer radio can help tryng differnt ratios to get the desired results. Although I'm bored watching all the Extras and Sukhois doing their thing I still love seeing a properly set up aerobat doing rolls at low airspeed as if there's a string right through the spinner to the tailpost. Mitch

Thomas B

My Feedback: (4)

I think you might find that airplanes of the 1930's vintage, Wacos included, often had the fin offset, per the link I supplied. Even the ground adjusted trim tabs were a nod towards reducing the pilot workload and trim need.

In fact, the Curtiss P-40 had a 1.5 degree fin offset and it is of the same vintage as the Waco, pretty much. Yes, it had much more power. By your logic, the P-40 pilots should have had straight zero-zero-zero aircraft and flown and trimmed as needed....

Lots of airplanes have some trim and thrust line adjustments made, so the aircraft is close to what it needs to be in cruise, where most of it's time is spent in typical operations. This minimizes the pilot workload, including trimming, in normal flight. You can never get rid of all of it, but it can be reduced.

Thrust line adjustments became trendy later, to be sure.

I would certainly agree that a Masters class/Top Gun scale entry needs to be scale in reguards to thrust line. However, the vast majoity of models being discussed in this thread will never be flown in competition.

Stickbuilder

You are absolutely correct.

What will you do when the day comes that you wish to become competitive, and you have never learned to truly fly the airplane, and you can't have the crutches built it? Will you have to learn to fly all over again? As I said, I don't use them, nor do I nail the throttle. I try to fly within the scale envelope at all times.

So with all that being said, you do it your way, and I'll do it mine. We can still be buddies. When are you going to request membership in the Brotherhood??????????

Bill, AMA 4720
WACO Brotherhood #1

WacoNut

For what it's worth I am installing my 50cc engine at zero/zero,
To me it looks like the Waco has large enough tail surfaces to keep the thing going nice and straight(as long as you build it straight) and tourque will still be an issue even with some degree of thrust angle adjustment. I think this is just part of what makes flying a tail dragger fun. Learn to fly with the rudder and enjoy.
Has anyone tried to side slip their Waco?? I like doing that with my 1/4 Cub(high wing thingy with a pancake motor as Bill calls it)just not sure if I will have the guts to try it with the Waco. Also how does the Waco react to spins? I like doing scale aerobatics.
Later!!
Anthony

khodges

My Feedback: (1)

It may be different with these models set up a bit differently and the variation in weight. (As I said mine is on the heavy side, at a bit over 18 pounds). I have spun mine once, and I hope never to do it again, whether intentional or not. As I said earlier, full power application at low airspeed makes this thing want to snap to the left. The plane is rather short coupled, so it will pitch or yaw readily with minimal control input. I was fairly high, and was testing my stall characteristics. I had raised the nose,and throttled back, and when I saw a pre-stall wing waggle, gave it power too fast and it snap rolled left into a fairly flat spin. I gave full right rudder, down elevator and pulled back power. It came out of the spin in a vertical dive (got the airspeed up) and I pulled out with moderate power about 30 feet up. It did three quick turns betwen the snap and recovery. I'm not very comfortable with spins, especially unintentional ones, so maybe this wasn't so bad. But I sure landed as soon as I could so I could change my drawers.

Loops, rolls (axial and barrel), stall turns, wingovers, split esses and Immelmans are great. I don't try inverted flight because it isn't prototypical for this plane (other than the inverted portion of loops and rolls) because the fuel system wouldn't operate properly without positive G. I think the barrel roll is the prettiest maneuver this plane does.

skylarkmk1

Ken and the rest of you interested in the Vertical Fin offset question and rudder trim tabs,

Back on page 124, post 3097 is the start of a short disscusion on the fin offset on the UPF-7s. WacoJoe (our resident Full Scale UPF pilot) was interested as his does not have any offset. Post 3102 is what I have been able to find out about the offset.

Page 124, post 3100 starts the trim tab discussion. Post 3107 continues the discussion on the use of the tab an a R/C model.

Thomas B

My Feedback: (4)

As vintage aircraft were rebuilt over the years, the original fin offsets and even thrust lines were modified more than folks would care to admit to the FAA... I have no doubt that a number of Wacos were modified along the way.

I have heard that some remove the fin offset because of the weird look that it has. Per that link I posted earlier, some add it later.

For instance, even though the Piper Super Cub has 4 degrees of down thrust, many rebuilt ones over the years quietly had their downthrust completely removed. This had a great improvement on the short field performance. Only recently did an STC get formally approved for a motor mount that takes out the downthrust.

Thomas B

My Feedback: (4)

How do you know I am not already competitive, flying skills wise?... Is this a good place to mention that I have a private license with around 500 hours in single engine land aircraft and sailplanes? And that I have a pretty decent record of R/C aerobatic, R/C team scale (pilot half of the team) and other competition awards from years past?

I think a good pilot can perfectly control any airplane whether the aircraft has any thrust line of fin offsets, or not. I certainly know that I can... He is instinctively doing whatever it takes to make the aircraft perform as desired. The "crutches", as you call them, disappear into the "background noise" of flying the aircraft.

However, I have flown a number of aircraft that really needed some thrust or fin offset. I have about 25 hours in a Varga (Shinn) 2150A. In an extended climb, it took a significant amount of rudder pressure to keep the ball in the center (150 hp and kind of short, tail moment wise). Some thrust offset or fin offset would have been nice to have...not required, but nice to have.

The "crutches", as you call them, simply reduce the pilot workload a little, be it full scale or R/C model. It does not subtract from pilot skill, once the pilot has some varied experience in different aircraft.

No reason at all not to be freinds and we can certainly agree to disagree... And I am indeed a member of the Waco brotherhood, number 89.

Thomas B

My Feedback: (4)

Getting back to Wacos...I ran across this nice pic of Mike Barbees big Genesis 1/3 scale Waco YMF-5 in the pits at Top Gun 2008 a couple of weeks back.

5th in Expert class this year......

Stickbuilder

Thomas,

If you would look back a few pages, you will find several photos of not only Mike Barbee's Genesis, but also Bob Gonzalez' as well. I spoke at length with both of them at Top Gun in between judging chores. There are over 100 detail photos of Mike's Waco Classic here in this thread. If you need more, I've got them, and will be happy to either post them, or e-mail them to you. And you don't hold the patent on being a full scale pilot. There are several of us here in the Brotherhood. Some of us even hold some interesting endorsements. And some of us (really old Farts) have several thousand hours of stick time. That don't mean diddly squat in the Brotherhood. We are all knee knockers when we ease the throttle in on the YMF/UMF models. As the man said, It is preferrable to break ground and fly into the wind, and not vice-versa.

Bill, AMA 4720
WACO Brotherhood #1