Tabloid, Camel & Snipe
 

The photo below shows aircraft attending a little BBQ luncheon last Saturday. The three WWI aeroplanes are resident at the field and were flown in a demo that morning. I'm working on posting a video of the flight. The photo is just a preview if I can learn to make friends with Mr. Youtube.

Dick


http://www.rcuniverse.com/forum/atta...mentid=2002836

Nice shot! Is that Mike Coutches P-51H staring straight at the camera?

It was a P-51H all right, but I didn't know the owner. The plane flew in from Hayward, CA if that's any help.

Yep, that would be Coutches' airplane. There are only two H model Mustangs flying so not too hard to keep track! The other one is in British colors so it's not difficult to tell them apart. I could tell the Mustang in your pic was silver just wasn't 100% certain if it was an H or not.

Nice. There is a couple of war birds and such but nothing like that here. How many of the WW1 planes are the Aerodrome replicas? Is that the NACA P-51?

I'm not familiar with Airdrome. The WWI airplanes in the picture are all replicas. I believe the Camel is by Jim Appleby and the other two were built by Antique Aero.

Don't know the history of the P-51. I had the impression that it was made from parts.

Dick

OK, here are some youtube links for short videos of the full size Tabloid, Camel and Snipe in operation. Each video is only a minute or two in duration. Other than general interest, the main reason I'm posting these videos is for people to hear the engine sounds, which are unlike any conventional full scale or model engine that you may have heard. I'll append each link with a short explanation of what you see and hear.

Be prepared for poor camera technique. This was my first attempt at using my wife's brand new camera. All I could do was try to keep up with the camera action with one hand while doing my crew member job with the other hand. It turned out to be nearly impossible to see the airplanes in flight through the viewfinder because I was looking toward the sun. No editing has been done at all.

Hope you enjoy this stuff,

Dick


First video: This is mostly a static showing the lineup of the Camel (on the left), Tabloid (in the center) and the Snipe (on the right). We are positioned on the dirt alongside the paved runway because the tailskids don't work well on pavement.

http://youtu.be/FvOboxSompQ


Second video: This shows priming of the Tabloid before starting. The engine has been turned slowly until each exhaust valve is open and then gasoline is squirted into each cylinder with an ordinary squirt can. The engine is then turned several blades to distribute the fuel in the cylinders and let any excess drain out.

http://youtu.be/YJxaL9GqVLw


Third video: Starting the Tabloid. The Tabloid motor is a LeRhone 80 HP. We hear about how rotaries can't be throttled and can only be slowed by shutting off the ignition via a "blip" switch. Actually, not all rotaries are alike. In the case of the LeRhone there is a very primitive carburetor. A slide valve in the intake controls the amount of air into the engine and a variable nozzle controls the fuel flow. The pilot has two levers, one for air and one for fuel. He must carefully coordinate the two levers so the engine isn't too rich or too lean. There is also a blip switch to cut power for short periods. The engine is started with the air and fuel set to a minimum so the airplane doesn't run over the guy spinning the prop. Notice that you can see the engine itself spinning at the bottom of the cowl.

http://youtu.be/SpbvG2iB5dA


Fourth video: Starting and warming the Snipe. The Bentley motor is much larger than the LeRhone. It's 1550 cubic inches and 230 HP. It is throttled pretty much like the LeRhone. The occasional skip in running is a fouled plug. With the large amount of castor oil remaining in the cylinders after running, it's not uncommon to have a fouled plug on the cylinder that stopped at the bottom position.

About half way through this video you can hear a more raucous popping sound. That's the Camel starting up. The Camel has a Gnome 160 HP engine. Unlike the other two engines, the Gnome has no carburetor at all. The engine is throttled by shutting off ignition to selected cylinders with an interrupter device. The engine is started at full throttle (kinda scary for the guy flipping the prop) and then the pilot immediately cuts power back with the interrupter. You can hear a staccato popping noise as the Gnome runs on fewer cylinders.

At the end of the video all three aircraft take off. First the Tabloid, because it's the slowest. Then the Camel, where you can hear the engine throttled up by firing on more & more cylinders. Last is the Snipe, which is the most powerful and fastest. Both the Tabloid and Snipe sound fairly smooth as they are throttled up.

http://youtu.be/Nh1ZHv54U6g


Fifth video: This is a short segment which is largely out of focus. The camera auto focus couldn't cope with looking up into a mostly empty sky. I included the segment strictly so you could hear the Gnome engine run.

http://youtu.be/nMmah5ZOzKE


Sixth video: Snipe low passes, then Tabloid, then Camel.

http://youtu.be/Panfh0Cx3vo


Seventh video: Three ships in formation. Notice that you occasionally hear the popping sound from the Camel. That's because he's trying to maintain position on the slower Tabloid. The Camel pilot is having to cycle up and down in power to stay with the Tabloid. Notice also the stream unburned fuel/oil trailing behind the Camel.

http://youtu.be/Wbi3ZGdwe0A


Final video: Landings, parking & shutdown. Snipe lands first, then Tabloid, and finally the Camel. You can really hear the popping of the Camel as the pilot comes into parking position at lowest available power. The next step down in power is to blip the engine to kill power completely in short bursts. The Tabloid & Snipe are also being blipped for faster response power adjustments during tight maneuvering in parking. Remember, these planes have no brakes and minimal steering.

http://youtu.be/F8b71t_Qw1c

Cool stuff

Dick, very neat videos indeed! I've watched all the videos on YouTube of Kermit Weeks' Snipe and the engine just sounds spectacular. And while most of our model IC engines are pretty lame by comparison, I think my Seidel/UMS 770 gives a good show.

http://www.youtube.com/watch?v=nqhPjNADnBw http://www.youtube.com/watch?v=1Uczbrj7ZXY As they say: There may come a day when I will place an electronic noise maker in a scale model...but today is not that day!

+1

http://www.rcuniverse.com/forum/imag...quote_icon.png Originally Posted by TFF http://www.rcuniverse.com/forum/imag...post-right.png
Cool stuff



+1



Yes, I thought the sights and sounds were too cool not to share. I liked the sounds best of all. Too many modelers have heard mostly model engines run and thus have no basis of comparison when they say, "sounds just like the real plane". I hope WWI buffs will come away from this posting with a better understanding of what a real WWI plane might sound like.

Especially significant for me was the realization that not all rotary engines sound alike. Throttling by use of interrupted ignition sounds entirely different from throttling by use of intake restriction. As far as making a model sound like a full size plane with interruptor ignition, I think the only practical way may be through a "sound system". The technology today is probably insufficient to be considered accurate, but one can always hope for improvements in the future.

Dick