Atwood Wasp .049

Ken Cook wrote:             Jim, I don't know the size fields your able to fly it in. My field is quite small and I fly the Dakota. The Attwood.049 is a very anemic engine which makes it a good choice for small field flying. Don't offer too much nitro to this engine. They run just fine on 10% and it's much easier on the engine. I use the Cox black 6x3 series props for this engine. The Wasp isn't a barn burner as far as rpm's are concerned therefore propping in the size I mentioned seems fit. I do put the prop on backwards.

Ken,
Thanks for the info.  I'm not expected a whole lot from the engine.  I have access to a sod farm that would class as "moderate".  I've flown a lot of P-30's and short line towline gliders on the field.  Lost a couple of P-30's going off-field.  The primary motivation is to fly it at the FF Nats with another on-line friend who is a FFantic, This guy is more interested in the Classic era designs and engines.  While he does have an Atwood Shriek, he has no experience with the Wasp.  His only comment to me was that no one flew the A-Wasp after the Shriek, the Holland Hornet, then the Cox'es came out.  But it is period, and does match how the J-Hawk might have flown.  That's good enough for me this time around.

Ah, the Veco Dakota!  I flew the heck out of one of those with a Baby Bee back around '63.  Definitely not for competition, but lots of fun going in circles.  I actually have one of BMJR's Dakota reissues, but haven't gotten around to building it.  Most of my build time is dedicated to larger C/Ler's.

What do you run for oil in the A-Wasp?  I would probably use some of my Fox .35 fuel at 10% nitro and 29 % castor given the period for the engine.  I can shift to some 10%, and 22% half and half castor and synthetic.

Thanks

The Wasp .049 can be a hot little unit, but it (like Wen-Mac MK Is through Vs) is subject to rather extreme variances in performance due to paper gaskets (especially the cylinder to crankcase joint) and irregular fitment/wear in the cylinder annular porting. But a good one really does have nice power to weight ratio.

Hello Jim  
I have an Atwood Signature .049 that was assembled for performance at the factory. They were supposed to run beyond 17K Rpm. But I could not find in the paperwork accompanied with the engine the size of the propeller and that is the only engine I have with paperwork. They were made in .049 and .051 both anodized green heads. I also have the Wasp .049 and the Shriek .049 but haven`t used them on any model. Here are pics. of the Signature .049
                                                                                          Juan

F4D Phantom II wrote:Hello Jim  
I have an Atwood Signature .049 that was assembled for performance at the factory. They were supposed to run beyond 17K Rpm. But I could not find in the paperwork accompanied with the engine the size of the propeller and that is the only engine I have with paperwork. They were made in .049 and .051 both anodized green heads. I also have the Wasp .049 and the Shriek .049 but haven`t used them on any model. Here are pics. of the Signature .049
                                                                                          Juan

Juan,
Got it, thanks for posting.  This looks interesting and was probably intended to be an answer to the TeeDee or rumours of the TD.  Neat looking engine!
Jim

nice looking engine , don't know about the prop , looked but couldn't find any info on that ?!

What you have is a keeper for the curios cabinet. The primary improvements over the original Wasp design in the Shriek are the prop hub and crankshaft mods. They better distance fingers from prop arc and virtually eliminate crankshaft breakage from crashes.

Atwood Wasps were originally supplied with Kaysun 6-3 props. I don't know what (if any) props were included with the boxed Shriek, but I think that by the time Shrieks came out only OK Cubs were still being shipped with Kaysuns. I'd start with a Cox 6-3 for most any sport flying app. on any Atwood .049, but I'd just lube your Shriek and keep it. Find a rougher looking one if you want to run one.

Errata: We were talking about your Atwood Signature, not Shrieks, but my same observations still apply.

.051's were marked as .051

Nice engine!

F4D Phantom II wrote:Hello Jim  
I have an Atwood Signature .049 that was assembled for performance at the factory. They were supposed to run beyond 17K Rpm. But I could not find in the paperwork accompanied with the engine the size of the propeller and that is the only engine I have with paperwork. They were made in .049 and .051 both anodized green heads. I also have the Wasp .049 and the Shriek .049 but haven`t used them on any model. Here are pics. of the Signature .049
                                                                                          Juan

The November 1950 Air trails had the first review of the WASP.  It ran 11,600 on a wooden "wide Blade" 6x3 and 15,000 on a wooden 5x3.  They also said the engine would run 1,000 rpm faster on fuels designed for "miniature" engines.  True this may be anemic compared to modern 049s, but in the day it was spectacular.  It was the king of the hill until the Space Bug came out and then the Thermal Hopper beat them both out

Manufacturers were still fooling around with fuels to see what these little guys needed, but you can be sure modelers were pumping up the nitro.  K&B Supersonic 1000, a popular racing fuel was 50% methanol, 25% nitro, and 25% Castor oil.

Bob Holland was Bill Atwood's partner on the Wasp.  They got into a big argument when Bob found Bill was designing an engine for Wen Mac.  About 1953 they split up, Bob kept the WASP and the name, Bill Atwood went on to market his own designs, about identical to the original WASP.  Bob put a little "H" under the wasp name on the right of the crankcase to identify it as a Holland WASP.

We had Bob Holland as a speaker at one of the MECA EXPOs.  He said guys had been throwing blades on the 6x3 Kaysuns being supplied.  He had Top Flite make a special 6" prop for the engine and shipped them with the engine.  I had to search for years to get this prop!

It would be nice to find plugs for the Shriek. They seem to be difficult to source

I remember MECOA talking about a Shriek glowhead for years and never doing it.

Holland Wasp with 'H' stamp

That's pretty much typical MECOA style Mark. My Shriek sits on the shelf, plug is working but I know not for much longer. He's got big plans for a dying hobby.