lml@lancaironline.net Mailing List Archive

<<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> << Lancair Builders' Mail List >> <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> Sirs. I fly regularly with a friend in his LNC4 - IO550G Has anybody else experienced the following problem? Background: About 60 trouble free hours so far with never less than about 100 litres (25 gallons) of fuel on board. Fuel tanks constructed as per manual. Problem: Flying above field conducting NDB instrument checks with fuel down to about 80 litres (20 gallons) total (approx. 40 litres (10 gallons) each side). NDB checks concluded, reduce power and allow nose to drop for descent. Engine stops shortly afterwards! Change tanks, boost pump on, restart in approx eight seconds. Climb above field and conduct various checks - all opps normal. Reduce power and allow nose to drop again - engine stops again soon afterwards! Change tanks, boost pump on, engine restarts in approx. eight seconds again. Feels like twenty seconds this time. Power reduced to idle and conduct level glide approach and safe landing. Put aircraft to bed and scratch head for a while over cup of tea. Eventually conclude that fuel pick-ups in tanks were uncovered during both descents due to minimum dihedral, long tanks and relatively aft location of fuel pick-ups. All fuel system components and all other systems check out OK. Your comments gentlemen? Has anybody else experienced this? Do you agree with my conclusion? Responses to: khaydon@bigpond.com [...curious... 10gal requires a volume of 2310 cubic inches, equivalent to a structure 10" wide, 10" tall, and 23.1" long... seems to me the inboard fuel bay is smaller than this and would suggest that unporting the pickups with that much fuel available is unlikely, given the slosh door is functioning. Makes me wonder if the problem might not be with the vent system, as I heard that there was a discrepancy in the earlier manual which could lead one to miss the vent to that bay. Please cc: the LML when you respond to Kevin's private email, as he doesn't appear to be a subscriber, at least not with the email address given above. Thanks...... <Marv> ] LML website: http://www.olsusa.com/Users/Mkaye/maillist.html Builders' Bookstore: http://www.buildersbooks.com/lancair Please send your photos and drawings to marvkaye@olsusa.com.