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Introducing the Omega 1 - A Revolutionary Engine

TheFreak says...

No.

What kind of tolerances do you need to seal the chambers created by those rotors and then what happens to those tolerances from thermal expansion when the engine heats up?

Now ask yourself how you lubricate all of that and then notice the oil literally pouring out of the front seals of that engine.

All of those numbers are made up. Maybe someone did some creative theoretical napkin calculations but those numbers aren't based on anything that engine is doing.

LiquidPiston X-Mini 79cc SI Engine Animation

SFOGuy says...

"How is the engine going in durability testing? "We've been hyper-focused on proving the general operability, and showing that the engine works in these application demonstrators," says Shkolnik. "Now that it's pretty apparent that it's working, everyone wants to know how many hours can it run. We're working through that, it's part of what we're going to be doing over the next year. We're running engines for tens of hours, dozens of hours, we're not yet in the hundreds of hours where we want to be.

"We're not even running them long enough to think about things like seal replacement yet," he continues. "It's been a combination of little things we're addressing as we go along. "

Hmmm. So, not an actual engineer--why would a seal that's in the wall and has the rotor spinning past it do so much better than a seal which is in the rotor and spinning and spinning past the wall?

StukaFox said:

This response seems to have a few gaps in it, but here's what a company rep said:

"And then there's our apex seals, they're like our piston rings," he continues. "In the Wankel engine, they're inside the rotor, again. They move at a high speed, and bounce around, they're very hard to lubricate. In our case, they're stationary, they don't bounce around, and you can lubricate them directly from the housing.

"So we basically solved the key challenges the old rotaries had with combustion and with oiling. Those oiling challenges caused both durability issues and emissions problems. By making those components stationary, we solve the challenges of the old rotary. And we also upgraded its cycle to give it much higher efficiency."

https://newatlas.com/military/liquidpiston-rotary-x-engine-army-generator/

LiquidPiston X-Mini 79cc SI Engine Animation

StukaFox says...

This response seems to have a few gaps in it, but here's what a company rep said:

"And then there's our apex seals, they're like our piston rings," he continues. "In the Wankel engine, they're inside the rotor, again. They move at a high speed, and bounce around, they're very hard to lubricate. In our case, they're stationary, they don't bounce around, and you can lubricate them directly from the housing.

"So we basically solved the key challenges the old rotaries had with combustion and with oiling. Those oiling challenges caused both durability issues and emissions problems. By making those components stationary, we solve the challenges of the old rotary. And we also upgraded its cycle to give it much higher efficiency."

https://newatlas.com/military/liquidpiston-rotary-x-engine-army-generator/

SFOGuy said:

Someone tell me why the seals won't fail in the same way that Wankel rotors in the RX-7 do--but it will be a lot of fun until they do!

LiquidPiston X-Mini 79cc SI Engine Animation

Bad Rim Job

newtboy says...

Not only is there no rim left, there's no brake rotor or stub axle, even the upper A-arm is just gone.
Running from a hit and run I expect....or it's just a Wednesday in Florida.

Helicopter Rescue Accident

SFOGuy says...

Thanks for those insights---so, is NOTAR a bit less efficient in transferring power (ran out of horsepower to correct the yaw because of that?)

Or do you think it was just the gust was so large (the turbulence at a crest could have been ferocious) that it wouldn't have matter what model helicopter or whether it had NOTAR or a regular tail rotor--it simply would have been overmastered?

jimnms said:

It has a fan driven by the main gearbox. It's pretty rare for those to fail, but does spin like it lost control of yaw though. My first thought was since it's landing so close to the edge of that cliff, if the wind is moving from the right to left, there is going to be a big updraft coming over the cliff.

Watching it again, it looks like the pilot is having to fight some wind and seems to be having trouble keeping it down. Between 40-45 seconds, it looks like the wind changes as the helicopter appears to lift up and weather-vane into the wind just before losing control.

I found this video which is in German. If the Google auto-translate isn't too off, it says the cause is still unknown, but whoever they're interviewing at the end speculates that the helicopter was too heavy for the altitude it was operating at.

Whoa, We Did Not Realize Helicopters Could Do This

Helicopter Rescue Accident

SFOGuy says...

Cool pick up! But, doesn't NOTAR have a rotor IN the boom? Driving the ducted air that triggers the Coanda effect?

jimnms said:

That looks like an MD-900, which is a NOTAR, meaning it doesn't have a tail rotor.

Helicopter Rescue Accident

jimnms says...

That looks like an MD-900, which is a NOTAR, meaning it doesn't have a tail rotor.

SFOGuy said:

What happened? Bad luck with a tail rotor failure? Gust that caught and swung it? Looked like the pilot lost tail rotor authority slowly and it started to rotate and he did the smart thing; grounded it.

or I'm completely wrong.

Helicopter Rescue Accident

SFOGuy says...

What happened? Bad luck with a tail rotor failure? Gust that caught and swung it? Looked like the pilot lost tail rotor authority slowly and it started to rotate and he did the smart thing; grounded it.

or I'm completely wrong.

Skating the unskateable

SFOGuy says...

I assume (but don't know)---in the San Francisco sequence as he psychotically departs from the intersection of Hyde and Chestnut Street down the Hyde St cable car tracks towards the Ghiradelli Square/Aquatic Park area---that the black thing he is holding in his hand is some sort of control of for a disc brake on the rear wheels? The rotors and pads of which...would be glowing red hot and dripping bits of flaming debris as he comes to a stop before being mashed to by crossing traffic on Bay street at the bottom of the hill? Sort of like in those emergency runway brake tests they do for airliners?

ChaosEngine said:

ehmmm, how do you stop? The board won't ride outside the rail and you can't turn to scrub off speed.

Do you just hope for a kind run out and then bail?

Sikorsky - Boeing Future Vertical Lift

transmorpher says...

Looks like they've combined the rear rotor from the Lockheed AH-56 Cheyenne and the dual rotor design of Kamov helicopters like the Ka-50 Blackshark.

Which are both great things to have.

ant (Member Profile)

ant (Member Profile)

Helicopter Takes Out Row Of Portaloos

SFOGuy says...

This, weirdly, illustrates why rescue services (e.g. the Coastguard) will ask how many people the potential rescue might involve. Assuming the trouble is within the range of a smaller bird, they'll want to dispatch the smallest, most efficient helicopter for the lift, because the downwash of a big chopper's rotors does...well, this to the folks needing rescuing.



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