What Side Should The Door Be On?

[goldwing06]

I just happened to take pictures this summer.

excellent photo. it's clear that the engine is reverse rotation to the mustang. wondered about the cg adjustment that must've been necessary after the counter to single prop conversion. love the elliptical wings on the british fighters. beautiful to look at and a real pain to build with all the different size ribs.

 

[goldwing06]

Counter-rotating props are a great idea for getting power out of a big engine, but it's not without drawbacks.

1. Most obviously, they are LOUD. As each blade passes through the wake of its mate, the resulting "pop" becomes a roar.

2. There is a real potential for disaster in event of a gearbox failure. Imagine two props turning in opposite directions; if the gearset that provides the opposing rotation locks up, there's a strong probability the whole mechanism will explode into prop blades as they depart the hub, and the remainder of the hub disintegrates into small parts, better known as shrapnel.

i belive howard hughes experienced something of a problem with this while he was testing a new design. damn near killed him.

 

[Folks]

one last comment on engine torque, toward the end of ww2, large ice for aircraft had developed to the zenith of the technology for the era and were about to get very expensive for peacetime application but one last attempt to get the most effiencey, counter rotating props started to show up on several models of single engine ac. besides being more effecent, it solved the dangerous torque issue. it was a short lived solution because the jet age came along.

Yes we old coots are starting to bore others in effort to kill time till the Elio Team breaks for more news and advancements. Richard Bong, the highest scoring American WW II Ace was sent back stateside to preserve him for war bond sales and touring for the War effort. He just had to try the new Jet P-80 (F-80) Shooting star. The new P-80 had tendency to flame out on take off. YOu guessed it. Killed him out right. A witness said he was close enough to see Bong's desperate expression and struggling to jettison the canopy. Although I don't know what good popping the canopy would have done. I'm on record here in that torque was not that big a deal. YOu just had to deal with it. There were many more dangerous things that killed Pilots during the war. I met an old flight instructor that told me by far more pilots were killed from getting lost than were ever shot down or anything else. Go figure.

 

[Folks]

Counter-rotating props are a great idea for getting power out of a big engine, but it's not without drawbacks.

1. Most obviously, they are LOUD. As each blade passes through the wake of its mate, the resulting "pop" becomes a roar.

2. There is a real potential for disaster in event of a gearbox failure. Imagine two props turning in opposite directions; if the gearset that provides the opposing rotation locks up, there's a strong probability the whole mechanism will explode into prop blades as they depart the hub, and the remainder of the hub disintegrates into small parts, better known as shrapnel.

Yes, placing the prop in any other configuration than a huge tractor 6 blade resulted in too much of a dirty air compromise in eficiency. One wants clean air for each paddle at all times. A good illustration of a flawed design was the old B 36 Flying cigar. The rear facing props would create a drum beat of air on the wings that made a sound like no other from even 40 or 50 thousand feet. I doubt anyone hear remembers that sound. It was suffering from dirty air.

 

[skygazer6033]

I remember the drone of the B36. There was so many weird harmonic vibrations in axial counter rotating propeller designs most of them were very short lived. The Russians big Tupolev 95 is the only prop plane I know of that actually made it work. I've read that it is so loud that when our F15 guys intercept them where they're not supposed to be they can be heard inside the fighters from a mile or so away. I guess they're just so overbuilt they wouldn't dare break. I can also remember when some Reserve units and Air National Guard were still flying F4U4s and P51s. Nothing sounds like a Merlin.

 

[goldwing06]

I remember the drone of the B36. There was so many weird harmonic vibrations in axial counter rotating propeller designs most of them were very short lived. The Russians big Tupolev 95 is the only prop plane I know of that actually made it work. I've read that it is so loud that when our F15 guys intercept them where they're not supposed to be they can be heard inside the fighters from a mile or so away. I guess they're just so overbuilt they wouldn't dare break. I can also remember when some Reserve units and Air National Guard were still flying F4U4s and P51s. Nothing sounds like a Merlin.[/QUOTE
anyone who ever heard a b36 will ever forget it. one of the few round engines that u could not identify from the engine sound, but from the props. as far as the bear goes, it is still being intercepted off out shores today. f106's were intercepting them back in the 60's coming down by iceland, going to havana for their suntans and cigars. the 106 pilots took lots of pix of the intercepts and on the way back from cuba, they would stand in the observation bubbles and hold up schlitz beer, like a toast. night intercepts could get a little more hairy. but u r right about the noise from the props. that was one of the first things the 106 drivers would notice or mention when talking about the intercept.

 

[carzes]

Yes we old coots are starting to bore others in effort to kill time till the Elio Team breaks for more news and advancements.e.

Feel free to pass the time. I've always been facinated by aviation and av history, but in my socioeconomic bracket war stories are about as close as I'll ever get to the cockpit. Feel free to continue inspiring imagination.

 

[goldwing06]

Feel free to pass the time. I've always been facinated by aviation and av history, but in my socioeconomic bracket war stories are about as close as I'll ever get to the cockpit. Feel free to continue inspiring imagination.

with the elio's center line seating, i was thinking that a hud would be a nifty and functional alternative for an instrument panel. just to give u that aviation feel when driving. i suppose that after a while, it would just feel like the longest high speed taxi u ever did.

 

[Folks]

I remember the drone of the B36. There was so many weird harmonic vibrations in axial counter rotating propeller designs most of them were very short lived. The Russians big Tupolev 95 is the only prop plane I know of that actually made it work. I've read that it is so loud that when our F15 guys intercept them where they're not supposed to be they can be heard inside the fighters from a mile or so away. I guess they're just so overbuilt they wouldn't dare break. I can also remember when some Reserve units and Air National Guard were still flying F4U4s and P51s. Nothing sounds like a Merlin.

Kuel. They all have the same affect on me the steam locamotive included. I go running to see every time I hear one.

 

[goofyone]

with the elio's center line seating, i was thinking that a hud would be a nifty and functional alternative for an instrument panel. just to give u that aviation feel when driving. i suppose that after a while, it would just feel like the longest high speed taxi u ever did.

Even if we do get a not so great version of the Elgin as the final dash hopefully we will get an OBD-II port so we can use a head-up display such as the Navdy. With some sort of HUD installed I don't care what the dash looks like as I won't be looking at it much anyhow.

http://www.navdy.com/