Science Forums 2

[CraigD]

Originally Posted by Flying Binghi

Some extracts from Dieselair –
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At same fractional power, the diesel is as efficient as at full power. So maintaining cruise speed may require down to 50% of the fuel flow needed with gasoline engines operating at same fractional power, meaning so much more range.
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W W W . D I E S E L A I R . C O M -- The Diesel Air Newsletter -- Home

Very interesting references to what appears to be a recent resurgence in popularity of diesel aircraft! The 4-seat Diamond DA42 Twin Star in particular in a pretty amazing (with the addition of only a 26 gallon (118 L) added fuel tank, and throttled back to 42% power, in 2004 one made the first nonstop Atlantic crossing by a diesel airplane!), as is the Centurion 2.0 L engine system, which can be retrofitted into such popular light singles as the Cessna 172. I hope Thielert’s current financial woes present only a brief obstacle to the use of this remarkable engine system.

That said, I’m uncertain that, outside of a niche like light aircraft, diesel pistonprop are anywhere near as good as turboprop in any area other than purchase and maintenance cost, factors that are significant in the light aircraft market, but not very in the air carrier market.

Originally Posted by Flying Binghi

I would suggest Bio-diesel could be a replacement for Jet-A

An excellent suggestion, and one highly likely, I think, to be realized when a large, long-term increase in the cost of petrodiesel is clearly imminent or upon us.

The major challenge with replacing petrodiesel with biodiesel in aviation and other cold environment applications is its higher solidification (congealing) temperature. Unless a reliable technique of blending or cracking current biodiesel to overcome this issue is developed, a 90%+ biodiesel jet, turboprop, or diesel pistonprop all-season and commercial carrier altitude aircraft will need to have a fairly elaborate fuel heating and pre-shutdown flushing system. As these issues have been successfully addressed in other biodiesel, I don’t think this challenge presents a difficult barrier to biodiesel aviation.