Bob Holman 124" B-17
 

For a project further down the road and first 4 engine. Any experience out there on this one? I have 4 - .40 2-stroke engines that need a home. I wouldnt have to buy too much to do this one. I'm more interested in knowing if the .40s will fly it adequately and how it flys.
Edwin

RE: Bob Holman 124" B-17
 

Edwin, The airframe flys great. I reconfigurred and went up to .61's on mine. I found that the .40's had to run pretty hard. The larger motors run at a much lower throttle setting and my fear of overheating and high RPM are gone.
40's can and do fly it. Its a project to build as many parts don't fit perfectly. Keep the tail very light. I have 7 pounds of lead in the nose of mine, still flys like an oversize glider.
Read up on mine on my homepage. E-mail me if I can help.

RE: Bob Holman 124" B-17
 

Randy,
You are one persistant guy. Gotta admire that. You pretty much answered all my questions on your web site. I'm trying to get by without buying new engines. Better to keep looking.
Edwin

RE: Bob Holman 124" B-17
 

Edwin, I just can't bring myself to get rid of a good flying airplane...even after I crash it. When they fly this good you have to make repairs, sooner or later.

I've gotten a e-mail from a modeler that speaks of having a 99" span Wing Mfg short kit. Possibly you can find more info on one of those. It might fit in with what you want.

RE: Bob Holman 124" B-17
 

I've considered the wing mfg short kit. It looks like a fair amount of rework to make it more than a sport model. Flat sided nacells turn me off. I really wanted something more of a straight up build instead of re-engineering. But it looks like that one might be my only alternative. Before I do that, I might see if Bob can reduce his plans to about the wing mfg size. I could possibly use wings glass nose and cowls. Just kicking around the idea for now.
Edwin

RE: Bob Holman 124" B-17
 

Edwin, What motors do you have on hand? If they are powerful for their size and you build reasonably light ( especially in the tail ) the full size Holman plans will work fine. Mine would be a whole different machine if I could / would have kept a pound out of the tail area which caused the massive amount of lead in the nose. Under my circumstances my .61's work much better. 4 of the fp's or LA's would not be a good choice.

RE: Bob Holman 124" B-17
 

These are Tower .40s that I got in an estate sale. I beleive they are bushing engines. Probably just a little better than the FP engines but not real power houses.
Edwin

RE: Bob Holman 124" B-17
 

Edwin,
I would not use cheap engines on any multi engine plane. Not LAs FPs or off brand bushing engines. If you are going to use 2 strokes use a high quality ball bearing set of engines. Or if 4 strokes good name brand engines.
To build a model B-17 of that size you are looking at thousands of dollars. Don't go cheap on the most important part.


I have just passed the $4500.00 mark on my B-17 and she is not done yet. Multi engine stuff is not cheap.
I would hate to see you put all that work into a model and loose it due to engine failure.
Been there done that and will never do it again!
Hans

RE: Bob Holman 124" B-17
 

Good advice. I just need to look at my array of engines and figure out which way to go. To do a DS B-17 I would have to buy 4 engines. I have 3 saito 1.20s and 2 saito .56s. I prefer a straightup plans build the first time I do this. Looks like I need to look at scaling up a twinstar to 4 engine size and play with that while Im gathering equipment.
Edwin

RE: Bob Holman 124" B-17
 

Edwin, I built a twin engine "warm up" airplane to take with me with the B-17. I use it to do a flight of 2 before ever considering flying the 17. It gets me familiar with the flying site and shakes the nerves down.
I used my .60 size Midwest Ugly Stick plans and drew them up to an 81 inch span. I then made up some simple nacelles, redesigned the tail, and a fiberglass nose piece. It may well be my best flying airplane ever. I short tank one enging and fly single engine for practice but it nearly flys too good even on a single engine.. it would make an excellent 4 engine airframe.
I've built 2 of these..one for me and one for a good friend. I use 40's and he uses .60's, they both fly great. You have to actually fly 4 motor glow to understand the experience...so many checks, double checks, and then check again. Its great when it all comes together!

RE: Bob Holman 124" B-17
 

Are the plastic parts and cowls still available? What retracts were used on yours Randy.

Thanks,

Bill

RE: Bob Holman 124" B-17
 

Bill, I think a call to Bob Holman will get you the plastic and cowls. He responds much better to a telephone than e-mail. I've never heard of any shortage of parts.
My LG is fixed. I built the gear as shock absorbing and with the intent to have it retract someday. I will use electric jack screws should I ever get around to adding them.
I was browsing E-Bay one day and found a set of retracts made to fit the plans exactly. They were by a company named Robin something.. ( Robin aircraft, Robin machine, Robin retracts, etc ) Possibly a bit of searching on the Internet might find the company. I saved a photo of the set.

RE: Bob Holman 124" B-17
 

Here is the best shots I have of mine. As you can tell the Robin retracts would fit right in the narrow slot provided by the plans. Other than that, I would use Robarts and build the airframe to suit them. If you take on this project, it will be the least of your modifying. It doesn't go together like a kit...its more like an airplane that you actually build.
Hans ( Heavy Date ) may still have cowls or plastic. He started a Holman 17 but scrapped it and is building the much larger Don Smith project.

RE: Bob Holman 124" B-17
 

Thanks Randy. I have had the plans for a few years now and getting ready to vector them into the computer. This way I can change them and reprint for cutting. I found that century jet makes the retracts. Hey Hans you still have the cowls and plastics? If so email me.
[email protected]


Thanks,

Bill

RE: Bob Holman 124" B-17
 

I think the gear Randy is refereing to are "Robinaire". Here is a link:
http://robinairerc.20m.com/

RE: Bob Holman 124" B-17
 

Thanks Terry... I was actually pretty close to remembering what it was..I'm surprised!

I've heard tell that you have to say something out loud 3 times to remember it... There, I did it..now to wait a year and see what happens.

RE: Bob Holman 124" B-17
 

Bill,
I'll have to look around in that disaster area I call my shop, but I think I still have the plastic stuff and cowls.
Give me a couple of days to find them.
Hans

RE: Bob Holman 124" B-17
 

Thats the ticket. Sometimes the answer has to slap you in the face its so obvious. An ugly stick would make a great 4 engined test bed. I even have the plans in cad somewhere.

Do ya'll think there is much difference in handling between the Holman 124" and the Don Smith 138"?
Edwin

RE: Bob Holman 124" B-17
 

Edwin, I know for a fact that the Holman aircraft flys great..it could be no better. I've never flown a DS but I've never heard any discouraging remarks. I would have to assume that it flys ever bit as good.

I've got misc. pics of construction of my "Lindy Twin Stick" that I can send or post depending on intrest.

RE: Bob Holman 124" B-17
 

Thanks, but I can handle the ugly stick. But dont let that stop you from posting. I and others would still be interested in seeing them.
Edwin

RE: Bob Holman 124" B-17
 

Just got the plans and this is a big mother. Anybody converted this to electric? Any input greatly appreciated. Also, any suggestions for laser cutters?

TIA

Steve Snell

RE: Bob Holman 124" B-17
 

Steve,
I think that there was one converted to electric a few years ago. I guess it flew pretty well.
When I was going to do this plane I asked all the kit cutters about a kit and none would touch it. They said too many complaints about bad parts fit. I cut the parts myself and I see what they mean. Parts fit is terrible and I had to custom make most parts. That is why I trashed it and went with the Smith plan.

Hope it works out better for you.
Hans

Need cg location
 

Ryon, It has been a while, but I don't recall adjusting from the plans any. Do you have the Holman plans?

What is your situation if you don't mind? Bought a plane, building, drawing plans, etc?? I still recall my first flight, it was smooth.

Randy

This is the second Holman 17 I have built. The first one went to Arizona and the guy but electrics on it. He said I flew great. If you were happy with the CG I will leave it as per the plans.

Thanks

Ryon