Return-Path: Received: from pop3.olsusa.com ([63.150.212.2] verified) by logan.com (CommuniGate Pro SMTP 3.5.6) with ESMTP id 1110070 for rob@logan.com; Mon, 18 Feb 2002 23:48:50 -0500 Received: from siaag2ab.compuserve.com ([149.174.40.132]) by pop3.olsusa.com (Post.Office MTA v3.5.3 release 223 ID# 0-71866U8000L800S0V35) with ESMTP id com for ; Mon, 18 Feb 2002 23:45:43 -0500 Received: (from mailgate@localhost) by siaag2ab.compuserve.com (8.9.3/8.9.3/SUN-1.12) id XAA19552 for lancair.list@olsusa.com; Mon, 18 Feb 2002 23:48:08 -0500 (EST) Date: Mon, 18 Feb 2002 23:47:15 -0500 From: James Frantz Subject: Approach speeds in the mountains Sender: James Frantz To: "INTERNET:lancair.list@olsusa.com" Message-ID: <200202182347_MC3-F292-3EF9@compuserve.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=ISO-8859-1 Content-Disposition: inline X-Mailing-List: lancair.list@olsusa.com Reply-To: lancair.list@olsusa.com <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> << Lancair Builders' Mail List >> <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> >> >We put the LNC2 through its paces and came up with a dirty configuration= circle to land stabalized approach descending at 500fpm at 70KTIS. It stalls at 63KTIS< I realize that the above was information for dire emergencies however, we should make it clear that this is NOT an adequate = margin above stall in a Lancair during approach under any circumstance and especially in the mountains. The stalling speed of an aircraft varies depending upon gross weight, bank angle, and CG and other factors. The IAS meter has errors that are worse the slower you go and you can stall an aircraft = at any IAS up to its maneuvering speed. Let's assume the IAS was right on and the approach was = shot and maintained at 70 knots and the stalling speed for that approach was infact 63knots as indicated above. = A minor 1.25 "G" bump from a thermal or ridge lift during = approach WOULD HAVE STALLED this aircraft without = enough altitude to recover. = I'm especially concerned that the above approach = was a circling approach. A typical 20 degree bank would have reduced the stalling margin to only a few knots. In addition, this aircraft was operating well on the back side of the speed stability curve without enough = energy to stop the descent which is especially = dangerous if the engine quit or if this emergency approach was shot with a failed engine. I give forums on AOA flying at Sun'n Fun and Oshkosh every year. Because I'm an old mountain instructor and bush = pilot, we discuss some of the above issues. I invite you = to attend. Last year the Oshkosh forum counted towards the instructor's refresher. Tip ----- Always contact the ground at shallow = angles. Jim Frantz >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> LML website: http://members.olsusa.com/mkaye/maillist.html LML Builders' Bookstore: http://www.buildersbooks.com/lancair Please remember that purchases from the Builders' Bookstore assist with the management of the LML. Please send your photos and drawings to marvkaye@olsusa.com. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>