Thursday, June 5, 2014

Counter Rotating Choppers

There's a typically fun article in Popular Mechanics, the engineering cheerleader magazine with an astonishing history of not predicting the future. Pretty much anything they cover will not happen, ever. If they came out in favor of Global Warming the arguments would be over. Everybody would know it was fake because Popular Mechanics is always wrong.
 
The article is about full sized versions of those childs remote controlled helicopters with counter-rotating blades and a pusher prop on the rear. Turns out that Sikorsky and a bunch of other aircraft companies are building demonstration prototypes of these, full sized, for an alleged govt contract to replace the entire fleet of existing helicopters (this is the part that's most ridiculous) with three models of new Compound Coaxial Helicopters, CCH's. A scout gunship, a troop carrier gunship, and a heavy lifter. The big advantage is they can go 290-300 mph, which drastically extends their range over standard 170 mph standard choppers. Since commonly available missiles can hit airbases for helicopters, putting longer range craft that can VTOL in crappy field conditions outside the range of return fire is really important. And the military is always building the equipment it needs to fight the last war, since they can't predict the next one worth a damn either. We should have excellent long range rifles, helicopters, and FLIR and scout vehicles right about the time we leave Afghanistan where they would have been really decisive.
 
Just in case you wondered, a few years ago Popular Mechanics insisted that the future of the military rifle was a short barrel subcompact XM-29 chambered in .223 (5.56 NATO) and an expensive and fatally finicky grenade launcher that kept killing operators and cost $150K each. Setting aside the grenades that didn't work, an educated editor would have noticed that a high velocity rifle caliber in the machinegun requires a long barrel to work properly, so making that caliber work in a short 10-inch barrel at pressures which don't melt the steel and ruin it? Fail. You CAN overpressure the round and melt the barrel to get the velocity with very light bullets, but I've seen wonderful pictures of service rifles with bullets burned through the side of a rifle barrel because the troops in Afghanistan use 80 grain extra long bullets to hunt Kevlar armored Taliban. It isn't working. They mostly downgraded to (circa 1960) M14s and 165 grain .308 bullets, since the armor slows those down sort of like butter does. Which is to say: "not at all." This is the big reason why survivalists use full caliber rifles. Armor is a security blanket, which is to say entirely delusional. That and you can't eat a deer hit by a .223. Too many bullet fragments in the meat. 10 years ago, Popular Mechanics was sure that the XM-29 was the future rifle for the US military. They were wrong.
 
Popular Mechanics also predicted adoption of flying wing planes, and nuclear fusion by 1960 providing the world's electrical power. Flying cars like the Jetsons, and all sorts of amusing errors. They've got a serious track record of being wrong. And this is a shame because the various CCH aircraft are pretty cool. The Osprey rarely works right. I would rather walk than get a ride on one. I wouldn't want to be within half a mile of one landing. They tend to hit things, those big rotors, or rotate wrong and explode. They have a lot of nasty problems the engineers should have fixed before building production models. Some of the aircraft in the article are supposed to correct that.
 
When I first learned about Ground Effect Planes through a TV broadcast from Redwood City, a local aircraft engineer had a working model sea-plane. The Russians have a huge one, the Ekranoplane, intended for the invasion of Sweden during the Cold War, but naturally it was never used. In the real world, putting an aircraft close to the water is an excellent way to dip a wingtip and crash. It is a shame, since the idea of powering an aircraft with a common truck engine rather than an exotic aircraft engine is encouraging. Naturally, the idea of a plane that only works on seas that were absolutely calm is pretty dumb. These CCH helos would probably be better. Not any more fuel efficient other than the increased speed and range, but my coastline does need long range aircraft for Life Flight, priority/urgent delivery or transportation, search and rescue for the coast guard since getting capsized on the Pacific can be a life ending experience. The water is really COLD. 54'F is hypothermia in minutes. And there's great white sharks too. Big ones. Bigger than the movie Jaws.
 
I'm not opposed to new aircraft. I think these have potential. They work great as RC models. I'm a mile from the old landing strip of aviation pioneer Lyman Gilmore. He was local. Opened the first commercial airfield in 1907. The strip is abandoned, but its still there, under the weeds. The newer county airport is a few miles Southeast of there, on a higher plateau with better visibility and no houses to crash into. Lots of retired air force pilots end up here because the airport is low-key, the rents are cheap for hanger space, and you can even buy a place with access, so you have a hanger with taxiway directly off the back of your place. Those houses go for a premium, but if you like to fly, you can put a garage door opener in your plane. Picture that. It's a thing.
 
An aviation engineer is opening a plant for stubby sports aircraft in Vacaville, at the strip next to The Nut Tree. The Nut Tree was the last place you could pee at the edge of the Bay Area, because there are no rest stops in the metropolis. Lots of restaurants etc, but no rest stops. Dad used to fly us (more often just me) in a rented Cessna from Santa Rosa to Vacaville airport, back when he was into flying. It is an expensive hobby. These planes are meant to be cheaper, and the company helps train pilots to fly these slow, high lift planes which can take off and land on water or on land, depending on gear. They have a pusher prop.
See, this sort of thing is more useful for adventuring hobby pilots than really expensive counter rotating helicopters. I suspect we'll get them anyway, because even Popular Mechanics will get it right, eventually. Maybe not all at once. Those sorts of things are extra loud, and you could probably target AA guns using the noise. I suspect the military would be less than impressed with them. In the end, the existing rotary aircraft will continue to be used because they are cheaper than new aircraft for missions that don't matter anymore. We aren't a world power, not really. We're adventuring, and if we're adventuring we should be letting the corporations do that on their own dime, not our taxes.
 
Considering the sweet homebuilt experimental aircraft I get to see at the local airshow, I think leaving these sorts of developments to rich engineers with small budgets is better. Expensive aircraft mostly crash. Small engineers are more careful because they're the pilot. They have motivation to be smart in both design and craftsmanship. It is a matter of vested interest.
 
While the kid in me loves the warbirds and the experimental planes, and the engineer in me marvels at the bodged in fixes for stuff that shouldn't have been built in the first place, I still like air shows, and aircraft. I don't care enough to actually pilot something. I feel best on the ground. But they're neat to see on the tarmac or pirouetting overhead. I'm fine with that. Science marches on.

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