Dawn Patrol @ WPAFB/ replica Scale...

Hey Guys,

I made it up to the Dawn Patrol @ WPAFB over the weekend. I grew up in dayton, and used to spend a bunch of time at the museum. I've always been a fan of old planes, but had never really had the chance to see much WWI era stuff (or replicas) that actually flies. That was definetly cool to see.

Anyway, I had a question about the replicas. It seems like a large percentage of the kits/plans are smaller than full size. What's the reason for this? I could understand if you were trying to save weight to get under the ultralight weight, or if the planes were high powered to begin with, and you wanted to use a smaller power plant. I can't seem to come up with a good reason why you would build a Nieuport 11 in 7/8 instead of full scale.

Also, I live in Gatlinburg, TN (near knoxville). Is there anyone in this general area who is building or flying? I was reading about building the stuff on www.nieuports.com, and it really doesn't look that bad. I'd love to check out someone elses project. My uncle is building a piper cub replica up in ohio, and Graham Lee's planes look like they are a lot closer to my skill level, since they seem to require more rivets, and less welding.


Pete

Graham Lee's Nieuport was designed to meet Canadian ultralight regulations. Although the plane is dimensionally built to 7/8 scale, it is much, much lighter than the original plane. Graham's prototype weighed something like 270 lbs empty, and IIRC was powered by a 430cc Cuyuna two-stroke with a homemade reduction drive.

Even the somewhat heavier VW-powered birds only weigh in the neighborhood of 400 lbs empty.

I didn't realize that the prototypes were that light. I'm not sure about the originals, but I would guess they were at least 1000 lbs or so.

Are there other gatherings/fly-ins/Airshows around the country, or is the Dawn Patrol @ WPAFB pretty much it?

[Brad]

You are pretty close on the original weight. I'm not 100% certain why Graham chose to build in 7/8 scale, but it works out wonderfully. It is large enough for all but the very largest of pilots. The 7/8 can, if built with care, be completed as a US legal ultralight, but just barely. He does also have a full scale version.

Unfortunately Graham passed away this past weekend. I'm certain his son will carry on providing his plans and support for builders, and there is a VERY strong community of builders out there. I highly recommend this replica (7/8 OR full scale) to anyone looking to build a Nieuport... or in my case a Siemens-Schuckert DI.

There is a fly in every Fathers' Day weekend at Gardner, KS for WWI replica builders. It is a real blast, and a lot of good information can be had there. Robert Baslee of Airdrome Aeroplanes is always there, as are the KC Dawn Patrol guys. It is probably the largest "regularly scheduled" annual gathering of WWI replica builders, although it isn't a huge venue like Oshkosh.

Brad

Great show. I went to the Dawn Patrol at WPAFB as well. I still feel horrible for that guys' poor N-28.

It is my understanding that it all has to do with weight. If built to full scale most planes would require a much, much larger engine. In the cases of the Se5's, they would need twice the engine size. Cost, maintainence, and overall headache is a lot less........................ so the pilots where saying.

[Jeff Brooks]

I read this explanation somewhere on one of these threads, the engine output of the old rotary/radial engines is actually better than modern engines.

The old engines develop their horsepower at lower RPM, this means they have the torque to turn a larger prop. The larger prop has more thrust to push/pull the plane.

The modern engines develop their horsepower at twice the engine RPM so the prop they use must be smaller. A modern engine in a full scale replica usually has too small a prop to have the same performance as the original engine. so you end up with sluggish performance.

Building the aircraft just a bit smaller in scale is one way to make the relative prop size with a modern engine more compatable with the replica, which give it better performance.

If someone were to manufacture a modern engine that has the torque output of the old 1914-1920 engines, but the reliability of a modern engine, there might be more full scale replicas flying out there!

[Brad]

Originally Posted by Jeff Brooks

I read this explanation somewhere on one of these threads, the engine output of the old rotary/radial engines is actually better than modern engines.

The old engines develop their horsepower at lower RPM, this means they have the torque to turn a larger prop. The larger prop has more thrust to push/pull the plane.

The modern engines develop their horsepower at twice the engine RPM so the prop they use must be smaller. A modern engine in a full scale replica usually has too small a prop to have the same performance as the original engine. so you end up with sluggish performance.

Building the aircraft just a bit smaller in scale is one way to make the relative prop size with a modern engine more compatable with the replica, which give it better performance.

If someone were to manufacture a modern engine that has the torque output of the old 1914-1920 engines, but the reliability of a modern engine, there might be more full scale replicas flying out there!

The relationship is something along the lines of if you double the size you need the SQUARE of the power. Half the size, square root of power. Engines big enough for full scale replicas are big and EXPENSIVE. Weight is also a factor- planes constructed as original are heavier, taking more power. "Ultralight style" construction takes less power even in full scale, but you still have to overcome the drag... and face it, WWI birds are DRAGGY. All those wires and struts make for a lot more power needed.

A 7/8 scale replica constructed ultralight-style (LIGHT!) only takes about half the power of the "real thing." That is why you see lots of Graham Lee replicas running direct drive VW engines- not very efficient, (power to weight, or specifically thrust to weight) and they would barely taxi a full-scale bird constructed in the original manner. Ditto for the 2 strokes some folks used.

That 1/8 scale reduction makes HUGE differences in cost and space needed to construct. It doesn't seem like it would, but it does. It also only requires half the power or even less to fly it. People say VW engines are 75 hp, but that is a load of crap... at the RPM they turn with a 60" prop, they are MAYBE 45 hp, probably less. Graham's original replica flew with a 27 hp 2-stroke using a belt reduction drive to swing a bigger prop.

Look at the weight you are dealing with, figure out the wing area for a proper wing loading, and scale accordingly... they see if it can be done. The 7/8 Nieuport (or in my case Siemens-Schuckert) is more than adequate for all but the very largest of pilots... and then it is a case of cockpit size, specifically legroom for the taller guys. I'm 5'9" and 250# (yes, much wider than average!) and I fit just fine in the 7/8 Nieuport built exactly per plans. I "tried on" Dick Starks's Nieuport just to be sure before I committed to this project.

It ain't rocket science. The power loading and wing loading of the 7/8 scale bird is about like a piper cub, maybe just a hair better. Performance is also similar. It doesn't glide as well, because it has more drag.

If ANYONE is thinking about a WWI replica and doesn't have the $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$ and dedication to build a museum quality replica like Achim and some of the others are doing, Graham Lee's Nieuport or Robert Baslee's reduced scale replicas are THE answer... unless you are a REALLY large guy... (or girl!) then the full scale versions that they have are the right choice. That isn't to knock the full-scale, authentic construction method guys... but you have to have a lot of dedication and skill to do the "authentic" birds. Virtually any "idiot" can build the Graham Lee or Baslee replicas.

Robert Baslee offers kits for an 80% DVII (still a BIG bird!) a full scale DrI, a full scale Eindecker, a full scale Nieuport 20-something, (sorry I forgot which exact one, maybe a 23?) and is working on a full-scale Nieuport 28!

He has kits for a 75% scale Eindecker, 75% scale DrI, 75% scale DVIII, 75% scale DVI (which can be detailed as a DVII, but that is about 65% scale I guess?) and can scale any of those up a bit if wanted.

Graham's son (since Graham passed away very recently) has plans for a full scale Nieuport 17 that can actually be built as anything from a Nieuport 11 to 27, or a Siemens-Schuckert DI. He has plans for the 7/8 scale Nieuport/Siemens-Schuckert and 7/8 scale Nieuport 12 also, as well as an unproven 7/8 scale Morane "Bullet." (No Morane replicas have flown yet. I seriously considered that one, but it needs some further development, a lot is left to the builder, and I wanted a GERMAN bird.)

The is a 7/8 SE5 or SE5a replica, done in wood like the original, but I don't know much about it... I don't even know where to get plans. A bit more complicated to build if I understand correctly.

The other full scale replicas are generally more "authentic." They are built using traditional methods, and take a LOT more time and effort to complete... but the end result is certainly worth it if you are that dedicated! Sands, Redfern, some others have plans available.

Brad