Long Distances in Light Aircraft
- Thread starter hambone
- Start date
ppragman
No pasa nada.
BEEF SUPREME
Well-Known Member
Usually there is a bunch of crap at the bottom of the tank that could mess up your engine. Sand, silt and other undesirable stuff.
jhugz
Well-Known Member
No, it's an unneeded risk. When would you ever cut your fuel reserves that close to need to run a tank dry, ever. Unless of course it's an emergency situation, well then everything goes out the window. In a fuel injected airplane you're susceptible to vapor lock and in a high performance airplane you're susceptible to abnormal temperatures.
Douglas
Old School KSUX
That is why I was told not to do it, yet in the twin it was cool to run the aux empty.
Kind of one of those deals where you just do whatever the owner or operator wants and stop asking questions.
ppragman
No pasa nada.
Here's why I've done it in the past. Fuel was critical on this flight, and I wanted to make damn sure that I had used all the fuel in the tank before I switched. My fuel reserves only gave me about a 45 minute reserve, and the weather wasn't cooperating as forecast. Better to burn it dry than to eat up your reserve with left over fuel at the bottom of the tanks. I've done this in high performance fuel injected planes no problem. Plenty of old timers have even told me that this was standard practice "back in the day." I don't particularly see how this is "unnecessary risk," its fuel management. I don't particularly think that I'd be doing it in turbo'd birds for reasons of cooling, but that's a little different than the standard IO520 and IO540s that I'm used to. The IO520 doesn't relight as fast as IO540 in my experience, but click the boost pump on and all your worries of vaporlock go right away. If it were as dangerous or scary as some people make it out to be, there'd be airplanes vaporlocking and falling out of the sky daily as pilots forget to switch tanks in singles and burn one dry.
ppragman
No pasa nada.
This should depend on where the pickups are in the tanks, and how much of the fuel is unusable. You have a fuel filter for a reason (not that you want it to get that far) but I don't think that's too much of a concern, you'd have to ask the wrench-types.
ppragman
No pasa nada.
TWA 800, is that you?
Apples != Oranges. That's a turbine critter, things work a little differently.
jhugz
Well-Known Member
There has been quite a few NTSB reports because of people screwing up a tank switch after running it dry. It's great if you do it and you feel comfortable w/ it but it's not something I would ever give as advice, and I still believe it's an unnecessary risk. Just because it worked for you last time doesn't mean it will again this time. When the manufacture recommends against an action, it's usually good enough reason for me not to commit the act.
ppragman
No pasa nada.
Certainly, people have frozen, or forgotten to switch back, or somehow bungled the restart problems. I also personally know someone who had one fail to relight on him. That said, it was an electric fuel pump failure to go along with it. Its useful under certain circumstances, including getting the maximum range out of your ship.
That said, I'd like to see where the manufacturer recommends against such an action. I've seen some manuals that say, "if it is desirable to run a tank dry in flight prior to switching tanks..."
jhugz
Well-Known Member
I'd have to find it but it's in one of Lycoming's engine newsletter thingy.
ppragman
No pasa nada.
If you can track it down, I'd be interested in seeing it, I'm always willing and able to change my opinion on stuff like this.
Tram
Well-Known Member
Had he become a statistic, wouldn't you have as well, or am I misunderstanding your story?
jhugz
Well-Known Member
http://www.lycoming.textron.com/support/tips-advice/key-reprints/pdfs/Key General.pdf
Page 18 I think, search for the word dry, it is in reference to fuel injected engines.
ppragman
No pasa nada.
Very interesting, I'm going to go through it a bit more thoroughly before I make up my mind one way or another, and also look for more information, however, yes, you are correct.
Straight from the horses mouth:
That said, they say other things in the article of disputed validity:
As required reading for any debate on this sort of thing:
http://www.avweb.com/news/pelican/182044-1.html
This (which is something I learned from the Deakins article several years ago) is critical to note:
Deakins also makes a compelling argument against the "crud" getting into the engine as well.
swisspilot
Well-Known Member
This is done all the time in places where AVGAS it`s not easy available. in the US pilots are spoiled in the rest of the world you will be surprise how hard is it to find AVGAS, in South America sometimes AVGAS is 200 miles away (Asia is probably worst), Jet fuel can be found a lot easier
USMCmech
Well-Known Member
If your fuel tank was that dirty then you have serious problems regardless. If there is that much crap in ther, then you need to fire your mechanic.
What little contaminates that are in the average fuel tank get mixed up during the flight, and is caught in th filter. This is also why I tell students not to sump the tanks if it has just been flown, even if there is crud in there, you're not going to see it in a fuel sample.