Jump to content


kent_island_sailor

Member Since 13 Jan 2006
Offline Last Active Today, 12:55 AM
*****

Posts I've Made

In Topic: DSC testing issues

Yesterday, 08:47 PM

Very cool. Now if we had ALE, HF radio use would be much easier still :)


In Topic: The diesel lie finally starts to unravel ...

Yesterday, 08:42 PM

Pumping loses = pumping AIR past a partly open throttle plate. Not related to fuel pumps ;)

Direct injection and high compression ratios are starting to blur the line between gasoline and diesel. Witness the Mazda SkyActive engines: Near diesel compression ratio and near or actual diesel economy on regular gasoline :D

 

BTW - Way back before WW II it was discovered, and then rediscovered again recently, that if you had very even mixture distribution in an aircraft engine, you could run them at full throttle and a very lean mixture. Combustion temps fall with all the extra air and economy is increased. IIRC, Charles Lindbergh was hired to teach this to pilots during WW II.


In Topic: The diesel lie finally starts to unravel ...

Yesterday, 05:59 PM

Diesels do not have pumping loses at part throttle and run very lean under 100% power, both are good for efficiency.

As for weight per gallon, diesel airplane manufacturers will sometimes publish range and GPH data based on #2 diesel instead of the Jet-A they would normally be fueled with ;)

* actual #2 diesel use in airplanes is temperature limited, it would be pretty hard to move it at 50 below zero temps


In Topic: The diesel lie finally starts to unravel ...

Yesterday, 04:26 PM

What diesel lie?

They were promoted as using less fuel than gasoline powered cars and they very much do.

Breathing after one goes by..............well maybe not so much. I spent a summer in London in the 70s and the all diesel cabs created air you could cut with a knife :o


In Topic: "Safe hull length" for a trip around Cape Horn?

Yesterday, 04:16 PM

Well full sized clipper ships have been done in by the Horn and if memory servers, A Catalina 27 or 30 made it by just fine. You don't need a long boat, you need a good boat. All that said, given the reasonable price of used boats today, I can't see much reason to dip below 35 feet and below 30 feet you are either going to be in a strong miserable slow boat or a lightweight boat performing a stunt instead of a voyage (see Catalina).

Don't forget it is COLD down there. I have no interest in doing the Horn myself because I would really get tired of being wet and cold when I could be in the tropics with rum. YMMV