Quantcast

Traveling with a twin engine 2 stroke airplane?

HomeBuiltAirplanes.com

Help Support HomeBuiltAirplanes.com:

blane.c

Well-Known Member
HBA Supporter
Joined
Jun 27, 2015
Messages
4,492
Location
capital district NY
For an aircraft designed for 170 ci, personally I doubt it will perform well with 35.44 ci. HP is just one number not the whole story.

Specifications (Rotax 582)[edit]
General characteristics
  • Type: two-cylinder, two-stroke, rotary valve, oil-in-fuel or oil-injected lubrication, dual carburetors, electronic dual ignition
  • Bore: 76 mm (2.99 in)
  • Stroke: 64 mm (2.52 in)
  • Displacement: 580.7 cm³ (35.44 cu in)
  • Dry weight: 50 kg (110 lb) with electric starter, carburetors, fuel pump, air filters and reduction gear
Components
  • Fuel type: premium unleaded: RON 90 octane or higher leaded or unleaded or AVGAS 100 LL
  • Oil system: oil-in-fuel (pre-mix) or oil injection
  • Cooling system: liquid cooled
Performance
Specifications (O-170-3 or A-65-8)[edit]
Data from Continental Aircraft Engine Operator's Manual[2]

General characteristics
Components
Performance
 

ragflyer

Well-Known Member
Joined
Apr 17, 2007
Messages
308
Got 67 power-loss accidents with Rotax 582s. The Rotax 582 does come out a bit better than the overall two-stroke results; about 32% of 582-powered aircraft accidents are engine related. Here's the breakdown as to causes:
Cause​
Count​
Undetermined​
28​
Engine Internal​
19​
Fuel - Engine​
3​
Fuel - System​
5​
Ignition​
2​
Reduction Drive​
4​
Oil Delivery​
0​
Carb Mechanical​
3​
Cooling​
3​
Three out of the four "Reduction Drive" cases were for belt reduction drives, not the Rotax gearbox. The fourth was due to corrosion in the "Power Takeoff Bearing" which may actually be on the engine itself.

"Fuel - Engine" is problems with the fuel system inside the engine compartment, while Fuel - Systems is for fuel delivery problems within the airframe. I do lump those in with the engine-related cases.

Ron Wanttaja
thanks Ron....much appreciated. The 582 seem better but overall cluster with other two strokes.
 

BBerson

Light Plane Philosopher
HBA Supporter
Joined
Dec 16, 2007
Messages
14,441
Location
Port Townsend WA
Running an engine direct drive may be a usable solution but it is not the same as derating. In fact it can actually increase stress on the engine if the BMEP is higher at that RPM.
Derating is normally meant as operating at less than rated power.
That could be either less rpm or less mean effective pressure. Do you have any reference of an aircraft engine damaged by operating at half power with high mean effective pressure?
 

BBerson

Light Plane Philosopher
HBA Supporter
Joined
Dec 16, 2007
Messages
14,441
Location
Port Townsend WA
Two engines doesn't qualify for LSA in USA. Apparently, the FAA didn't think twins were overall a value to safety.
 

EzyBuildWing

Well-Known Member
Joined
Sep 23, 2009
Messages
135
Location
Sydney NSW Australia
Kolb flyer....with twin German SOLO 13 HP direct-drive 2-strokes....... would obviously be better/safer as a tri-motor.



For flying over desert like this, 3 obviously better than 1 or 2.....

 

Bille Floyd

Well-Known Member
Joined
Sep 26, 2019
Messages
406
...

A twin does not increase reliability, it doubles the likelihood of an engine failure. The safety benefit of a twin comes from the ability to keep flying and ideally still climb on one engine. Without folding or feathering props, that can be a real challenge.
What If :
The two engines, both interface with the same PSRU, and both engines
had a clutch, to disengage at any moment needed ? Now you have one
prop, that doesn't need to feather , (it might need to be in-flight pitch adjustable though).

Bille
 

akwrencher

Well-Known Member
HBA Supporter
Joined
Oct 16, 2012
Messages
1,314
Location
Gustavus, AK
Yes, would need inflight adjusted or you wouldn't be able to use the power from one engine. Also, easier said than done. The basic setup would not be a big feat of engineering, but making it reliable could be......
 

akwrencher

Well-Known Member
HBA Supporter
Joined
Oct 16, 2012
Messages
1,314
Location
Gustavus, AK
That's a cool little plane. Reminds me of one of Fritz W's renderings, the one tube fuselage.
 

Sockmonkey

Well-Known Member
Joined
Apr 24, 2014
Messages
2,027
Location
Flint, Mi, USA
Since engines and aircraft are created by humans, any failure is thus human-related. Humans designed them, humans built components, humans assemble them, and humans operate them. On that basis, 100% of all accidents, not just engine failures, are "human related." Guess I should just delete my databases and relax.
This is being needlessly pedantic. The point is that unlike freak weather, you can eliminate engine failure as a likely danger by just doing proper maintenance.
 

Wanttaja

Well-Known Member
Joined
Sep 15, 2013
Messages
1,661
Location
Seattle, WA
This is being needlessly pedantic. The point is that unlike freak weather, you can eliminate engine failure as a likely danger by just doing proper maintenance.
"Eliminate" seems needlessly optimistic. Parts break, and routine maintenance doesn't always prevent it. I once had a bolt shear in half on my tailwheel spring bracket. Under a microscope, there was an obvious rusty line on the broken face showing where corrosion had advanced. No way it would be detected under normal maintenance. But perhaps "proper" maintenance would have included complete disassembly of the aircraft.

Four stroke engines have dedicated systems to put oil where it is needed. That's one reason they're heavier and more complex than two-strokes. But they do seem to have fewer seizures.

Ron Wanttaja
 

Sockmonkey

Well-Known Member
Joined
Apr 24, 2014
Messages
2,027
Location
Flint, Mi, USA
"Eliminate" seems needlessly optimistic. Parts break, and routine maintenance doesn't always prevent it. I once had a bolt shear in half on my tailwheel spring bracket. Under a microscope, there was an obvious rusty line on the broken face showing where corrosion had advanced. No way it would be detected under normal maintenance. But perhaps "proper" maintenance would have included complete disassembly of the aircraft.

Four stroke engines have dedicated systems to put oil where it is needed. That's one reason they're heavier and more complex than two-strokes. But they do seem to have fewer seizures.

Ron Wanttaja
I did specify that it made such failures unlikely, not impossible.

Anyhow, are there non-diesel opposed-piston two-strokes?
 

Werner

Active Member
Joined
Jun 13, 2012
Messages
33
Location
Ortisei Italy
Top