What is HFE and what are the benifits

[Rick1999]

A BREAK THROUGH IN HEAVY – FUEL TECHNOLOGY!!

3W –MODELLMOTOREN GMBH

Proudly announces the development of a family of 4 Heavy –Fuel –Engines:
3W – 28i HFE / 3W- 56iB2 HFE
3W – 110i B2 TS HFE / 3W – 157 XI B2 TS HFE

Some highlights:

• Standard cylinders and pistons are used .The same we use for our gas engines.
• Standard 3W-ignition (s) with standard spark plug (s).
• Modified standard diaphragm carburettor.
• Special air intake system.
• Cold start system using cartridge heaters only for the cold start.
• Special mufflers or headers.
• Fuel used for testing: JET A-1 with 5% oil.
• No power loss compared to gasoline engines.
• HFE engines run 30 - 40°C cooler than gas engines.
• Running characteristics are soft due to the lower compression compared to gas engines.
• The modified carburettor operates like a mechanical fuel injection system in combination with our air intake system.
• More details have to be discussed personally.

Some test results:
3W – 28i HFE:
Stable idle: 1500 RPM
Max. RPM 10.000, no drop in RPM was noticed during a 10 min test run
3W-56i B2 HFE:
2 x 3 hrs test run with 6600 RPM, no drop in RPM was noticed
Other 3W-engines can be converted to HFE upon request or custom made engines can be designed.

[Rick1999]

Anyone with any ideas?????

[castlebravo]

Sounds like a psuedo-diesel conversion.......would be nervous of the longevity.


CB

[BTerry]

"Heavy Fuel" is a kerosene-based fuel, so it is related to "diesel". More specifically it refers to jet fuel, either Jet-A or more likely JP-8, which is the military version of Jet-A. It is used in helis, jets, trucks, generators, heaters, stoves, etc. in the "overseas contingency areas". The stuff is much easier to obtain than gasoline in that instance.

For benefits, besides accessibility in "certain parts of the world", it runs a bit cooler than gasoline and gives a longer run time per unit weight than does gasoline. Kero-based fuels have a higher lubricity than gas, so that will help with longevity.

In other words, it is GREAT if you are flying for many, many hours per flight in a "certain" location. Otherwise, it may be possible to cut a bit of fuel load weight while simultaneously running cooler. FWIW home heating oil may work in these engines as well. If so, we can be enviro-weenies and run soy-based "bioheat" through these engines. Just a thought...

[BigBird]

	Quote: Originally Posted by Rick1999
	Anyone with any ideas?????

These HFE engines are developed to meet strict requirements set by the DOD. All UAV's must run on JP-8. This way the military only has to carry one type of fuel for everything.
3W is just offering them to the model aircraft industry as an option. Not a very good one in most model aircraft. Oily mess and in most cases hard to get fuel for.
JD

[RTK]

There is one guy on these boards that has been playing with them for a long time already, don't know if he will chime in.

[Mithrandir]

	Quote: Originally Posted by BigBird
	These HFE engines are developed to meet strict requirements set by the DOD. All UAV's must run on JP-8. This way the military only has to carry one type of fuel for everything. 3W is just offering them to the model aircraft industry as an option. Not a very good one in most model aircraft. Oily mess and in most cases hard to get fuel for. JD

Predator A (MQ1) uses Av-gas.....

true.. they prefer HF, but in 1994, there was no other UAV that was reliable... 'cept the Predator