Jet-fueled 2-stroke diesel V-4

[freebeard]

DELTAHAWK Diesel Jet Aircraft Engine - ENGINE WEEK 2024

Low maintenance with mechanical direct injection with one pump and injector per cylinder for redundancy - no cams valves or electronics.

Dry sump lubrication and apparently the combustion air never enters the crankcase, so no oil mixture fuel and it will operate inverted or standing on it's end for a helicopter.

2600 RPM redline --with power of a four-stroke with twice the displacement-- so it doesn't need a gearbox for propellers.

[cRiPpLe_rOoStEr]

DeltaHawk took a really long time to get the FAA certification. Truth be told, I would rather rely on a gear-driven blower for an aeronautic 2-stroke Diesel engine instead of the belt-driven one, even though it an automotive derivative of this engine would ever come to fruition the belt drive would allow for a variable-speed compressor to act like an EGR somehow. And since it relies on unit-injectors, wouldn't be rocket science to fit an electronically-controlled setup for compliance to regulations that a modern truck would need to address.

[Piotrsko]

FAA failure mode testing generally insures that a semi disabled engine will maintain at least 50% rated power for 30 minutes. That's in their published specs for test but they don't test for incomplete or broken assemblies.

Not sure what turbine requirements are, but I do know about frozen duck injestion: MacDac chicken room.

[cRiPpLe_rOoStEr]

I remember reading about the ability of the DeltaHawk engine to remain running after a belt failure, back in 2007 when I first found about this engine. Claims were the turbocharger could sustain enough pressure to keep it operating for a safe (well, sort of) landing.

[Logic]

Originally Posted by cRiPpLe_rOoStEr

I remember reading about the ability of the DeltaHawk engine to remain running after a belt failure, back in 2007 when I first found about this engine. Claims were the turbocharger could sustain enough pressure to keep it operating for a safe (well, sort of) landing.

This is a Sailplane or Glider:


No engine.
When you're landing; you're either landing, or you're landing..!
Yet; there they are, FAA etc approved.
How does that work!?

Sailplanes are like a bicycle with the chain removed:
You can go downhill; no problem.
It's only when you want to go uphill (and run out of momentum) that you miss the chain = engine power.

The difference between a chainless bicycle and a glider is that you; the pilot gets to choose 'The hills'.
ie YOU get to choose/make 'the hills', up or down, fast or slow with the joystick.
As long as you keep going 'downhill' enough to stay at an airspeed above stall (where the wings produce enough lift to keep you aloft) you're golden.

ie:
What an engine does for a plane, from a safety POV, is allow you to go:
"Oops! I've buggered this landing up!" 'Put the chain back on' = Slam on the power; climb, and go around and try again.
Now if the engine is running at half power; does it have enough power to climb that 'hill'..?
To me it seems like all the 'must have half power' regulation is... regulation for the sake of regulation.
All it really does is increase how far you can fly to find somewhere to (one chance) land.

So:
How is 'No Engine': Fine: Here's your FAA certificate.
but
If you happen to have an engine; it must keep working when half of it has caught fire and melted off..?


The other thing to consider:
WHO would you rather fly with:
Someone who learned to fly gliders 1st (and survived to get a glider's license) before getting a powered plane license.
or
Someone who thinks planes stop dead and just fall like stones as soon as the engine dies..? (exaggeration)

(They also know how to gain height, using vertically upward winds/thermals etc, which saves a lot of fuel!.

I have seen a Cessna 182 (generally considered under-powered) with 4 large men in it climb to 11 000 feet in a matter of minutes, then go where it's going fast, thanks to the trip now being all 'downhill'.
Piotrsko (if he's not too busy imagining seized solid engines) will tell you that that's not some you see)

[cRiPpLe_rOoStEr]

Once a military flight instructor from the Brazilian Air Force Academy told me he firmly believes gliding should be a part of fighter pilots training.

[Logic]

Originally Posted by cRiPpLe_rOoStEr

Once a military flight instructor from the Brazilian Air Force Academy told me he firmly believes gliding should be a part of fighter pilots training.

Yep!

It's also waaay cheaper to 1st get a GPL, then a PPL as there's less mandatory hours required for the PPL if you already have a GPL.
Well here anyway. I don't know about there?

[paniwew]

That engine design is seriously impressive—low maintenance, direct injection, and the ability to run inverted without oil issues? Sounds like a perfect setup for aviation or even military applications. The redundancy of a pump and injector per cylinder also makes it incredibly reliable. Would love to see how this performs in real-world testing.

[Logic]

Originally Posted by paniwew

That engine design is seriously impressive—low maintenance, direct injection, and the ability to run inverted without oil issues? Sounds like a perfect setup for aviation or even military applications. The redundancy of a pump and injector per cylinder also makes it incredibly reliable. Would love to see how this performs in real-world testing.

2-stroke diesels (direct injection) that use a turbo or supercharger instead of crankcase induction have been around and in use for years.
Detroit Diesel and MAN for a start.

You gain; cleaner burn as, like a 4-stroke, there is no oil being burned, using off the shelf parts.
You lose on; weight and size because of the added turbo/super charger.

But you can build a double acting piston engine with a 2nd combustion chamber below the piston!
A 1-stroke engine!
(Taller and oil reqd again. )

On the other hand; apparently the amount of lubrication oil required for crankcase induction/lubrication is dramatically less when there's no fuel also mixed in, so it's possible one might skip the extra weight and complexity of the added charger. with direct (fuel only) injection

Have you seen the clean, constant rpm 2-stroke (for Series Hybrid) thread?
That's light, obtainable, cheap, and easy!

[freebeard]

But you can build a double acting piston engine with a 2nd combustion chamber below the piston!
A 1-stroke engine!

Could you provide an example or illustration?