lml@lancaironline.net Mailing List Archive

<<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> << Lancair Builders' Mail List >> <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> Posted for "John Lasher" <johnlasher@msn.com>: I always thought that Lancair pilots are like fishermen and have a tendency to overstate their aircraft's speed. I have to admit that I don't leave the airplane at 75% power very long after arriving at FL 240 before going to LOP. I may be underestimating by a few knots; 288-290 knots is probably the best I could hope for. I use the VM-1000 to set the power and a RMI uencoder TAS readout. I have no reason to suspect bad TAS readings based on GPS GS readouts. Yes, based on the numbers I hear from Lancair pilots, I have a significantly slow airplane. I don't have winglets or deicing boots. I am the second owner of Walt Bills IV-P, N411WB. This was one of the early IV-P kits with a Dolly Parton cowl. The airframe workmanship is exceptional and got 5th place in Oshkosh in 1996. It has one of the best paint jobs I have seen on any Lancair IV. However, the avionics and power train needed work. The avionics have been upgraded to a beautiful panel with Garmin 530 and 430s. The engine is a TSIO-550B, which has some departures from original. It has an electronic ignition and a mag, new Ray-Jay turbos and intercoolers that probably came from the Malibu. Despite the differences, I expect that the engine is developing full rated power on TO and has no problem running at 75% rated at FL 240. This leaves the propeller, which probably is the reason that the aircraft doesn't fly as fast as most IV-Ps. The propeller is a McCauley 3 blade full feathering unit that I believe can be found on Cessna 414s. It seems to perform without problems, however, it was designed for a much slower aircraft, which might account for the 10-20 knots of extra airspeed that most IV-P drivers have over me. What about IAS? At FL 240 I see about 202 KIAS at 75% power ROP. Do you think the propeller is the problem? If so, what would you recommend? John Lasher LML website: http://www.olsusa.com/Users/Mkaye/maillist.html LML Builders' Bookstore: http://www.buildersbooks.com/lancair Please send your photos and drawings to marvkaye@olsusa.com.