Return-Path: Sender: (Marvin Kaye) To: lml Date: Mon, 01 Jul 2002 14:23:06 -0400 Message-ID: X-Original-Return-Path: Received: from [216.163.188.204] (HELO C9Mailgw03.amadis.com) by logan.com (CommuniGate Pro SMTP 4.0b4) with ESMTP id 1580686 for lml@lancaironline.net; Mon, 01 Jul 2002 14:14:46 -0400 Received: from c9service12.amadis.com (10.9.0.1) id 3CDE01B200465767 for lml@lancaironline.net; Mon, 1 Jul 2002 11:11:36 -0700 Received: from regandesigns.com (148.63.101.227) by c9service12.amadis.com (NPlex 6.5.012) id 3CFF8614000A2115 for lml@lancaironline.net; Mon, 1 Jul 2002 11:11:36 -0700 X-Original-Message-ID: <3D209C14.9040500@regandesigns.com> X-Original-Date: Mon, 01 Jul 2002 11:14:44 -0700 From: Brent Regan User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:0.9.4) Gecko/20011019 Netscape6/6.2 X-Accept-Language: en-us MIME-Version: 1.0 X-Original-To: Lancair Subject: Re: stall/spin testing Content-Type: multipart/alternative; boundary="------------010406090303000602030605" --------------010406090303000602030605 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Jim writes: << I refer you to Advisory Circular AC-90-89 page 5-9, the Amateur-Built Aircraft Flight Testing Handbook. Quote: Caution #1 -- If the manufacturer/designer of your aircraft has not demonstrated satisfactory spin characteristics and safe recovery, avoid all types of high angle of attack flight testing and placard the aircraft: "spins prohibited.">> (This is on page 54 of the AC (Page 61 of the pdf)). I was immediately struck by the phrase <> and wondered if this included landing. Reviewing the AC you will conclude that this statement applies to spin testing only. They are saying that if the manufacturer didn't spin test the design then neither should you. A reasonable position that I agree with. Earlier in the same document (Chapter 5, Section 2 starting on page 45 (Page 52 of the pdf)) is a very clear RECOMMENDATION for stall testing during hours 11-20 of a new aircraft's flight testing (with details on how to avoid spins). If the FAA's position was that you should not stall test an airplane that hasn't been spin tested then the warning would appear in the stall testing section and not later in the spin testing section. Perhaps the above quoted caution should be read "..avoid all further types of high angle of attack flight testing..", to be less confusing. Read it for yourself at: http://www2.airweb.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/1ab39b4ed563b08985256a35006d56af/d08fa9393154b636862569ba006f6d7f/$FILE/ATTLMVEO/AC90-89A.pdf Regards Brent Regan --------------010406090303000602030605 Content-Type: text/html; charset=us-ascii Content-Transfer-Encoding: 7bit Jim writes:

<<
I refer you to Advisory Circular AC-90-89 page 5-9, the Amateur-Built Aircraft Flight Testing Handbook. Quote: Caution #1 -- If the manufacturer/designer of your aircraft has not demonstrated satisfactory spin characteristics and safe recovery, avoid all types of high angle of attack flight testing and placard the aircraft: "spins prohibited.">> (This is on page 54 of the AC (Page 61 of the pdf)).

I was immediately struck by the phrase <<avoid all types of high angle of attack flight testing>> and wondered if this included landing. Reviewing the AC you will conclude that this statement applies to spin testing only. They are saying that if the manufacturer didn't spin test the design then neither should you. A reasonable position that I agree with.

Earlier in the same document (Chapter 5, Section 2 starting on page 45 (Page 52 of the pdf)) is a very clear RECOMMENDATION for stall testing during hours 11-20 of a new aircraft's flight testing (with details on how to avoid spins). If the FAA's position was that you should not stall test an airplane that hasn't been spin tested then the warning would appear in the stall testing section and not later in the spin testing section.

Perhaps the above quoted caution should be read "..avoid all further types of high angle of attack flight testing..", to be less confusing.

Read it for yourself at:
http://www2.airweb.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/1ab39b4ed563b08985256a35006d56af/d08fa9393154b636862569ba006f6d7f/$FILE/ATTLMVEO/AC90-89A.pdf

Regards
Brent Regan
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