X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Wed, 19 Aug 2009 13:01:26 -0400 Message-ID: X-Original-Return-Path: Received: from mta11.charter.net ([216.33.127.80] verified) by logan.com (CommuniGate Pro SMTP 5.2.16) with ESMTP id 3818040 for lml@lancaironline.net; Wed, 19 Aug 2009 08:35:45 -0400 Received-SPF: pass receiver=logan.com; client-ip=216.33.127.80; envelope-from=farnsworth@charter.net Received: from imp09 ([10.20.200.9]) by mta11.charter.net (InterMail vM.7.09.01.00 201-2219-108-20080618) with ESMTP id <20090819123509.GBEJ22327.mta11.charter.net@imp09> for ; Wed, 19 Aug 2009 08:35:09 -0400 Received: from Farnsworth ([75.139.158.86]) by imp09 with smtp.charter.net id WCb91c00B1s7vFP05Cb9CW; Wed, 19 Aug 2009 08:35:09 -0400 X-Authority-Analysis: v=1.0 c=1 a=hOpmn2quAAAA:8 a=vGf1tOB8AAAA:8 a=KMIu7TRDaQklWZLwk3oA:9 a=Yn2A2fVaRw6DDWdfjYEA:7 a=LUTmGeGlssQeb148UV0uvmxFFQcA:4 a=hUswqBWy9Q8A:10 a=igvvpczC94BxFQ2D:21 a=heXgzN5B1d5465eu:21 a=SSmOFEACAAAA:8 a=onC_jTWj7NouDhNskKUA:9 a=OSXhDA9vMvbz7wfj91cA:7 a=pPWPRCuOw_BDUqwRm1FkLY5Q0kEA:4 a=rgyluOk8XTARuhMm:21 a=CsvqJQwmctSYHktj:21 From: "farnsworth" X-Original-To: "'Lancair Mailing List'" References: Subject: RE: [LML] Re: Strength vs. stiffness X-Original-Date: Wed, 19 Aug 2009 08:35:17 -0400 X-Original-Message-ID: <90D7A89295404944893FCA06A709A2EF@Farnsworth> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_01DA_01CA20A7.FADF83E0" X-Mailer: Microsoft Office Outlook 11 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 In-Reply-To: thread-index: Acogt/hHhg6JVnUVRJWwontts5oEOQADqBPw This is a multi-part message in MIME format. ------=_NextPart_000_01DA_01CA20A7.FADF83E0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit _____ How hard was THAT landing? It wasn't the "hard landing" that caused the damage (the tail did not touch the runway); it was the oscillations that shook the tail that did the damage. The runway was short (about 2800') and the airspeed was higher than normal (long touchdown). The pilot elected to continue with the landing; hard touchdown (a normal landing flare would have made an even longer landing) and immediate hard braking. The touchdown started the tail oscillations. Under heavy braking the main gear started walking; the tail oscillations intensified, exceeding the aft fuselage strength. On Aug 18, 2009, at 1:32 PM, "farnsworth" wrote: Here are some scary pictures of vibration / torsion destruction of a glass airplane Here are the pictures of the Columbia 350 that broke it's tail upon hard landing and severe main gear shimmy upon heavy braking. No other damage to A/C. And, the tail never hit the ground. Purely violent shimmy did this.... _____ ------=_NextPart_000_01DA_01CA20A7.FADF83E0 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable

 

 

 

How hard was = THAT landing?

It wasn’t the “hard landing” that caused the damage (the tail did not = touch the runway); it was the oscillations that shook the tail that did the = damage. The runway was short (about 2800’) and the airspeed was higher than = normal (long touchdown). The pilot elected to continue with the landing; hard touchdown (a normal landing flare would have made an even longer = landing) and immediate hard braking. The touchdown started the tail oscillations. = Under heavy braking the main gear started walking; the tail oscillations = intensified, exceeding the aft fuselage strength.

 =



On Aug 18, 2009, at 1:32 PM, "farnsworth" <farnsworth@charter.net> = wrote:

Here are some scary pictures of = vibration / torsion destruction of a glass airplane =   

 

 

 

Here are the pictures of the = Columbia 350 that broke it's tail upon hard landing and severe main gear shimmy = upon heavy braking.  No other damage to A/C.  And, the tail never = hit the ground.  Purely violent shimmy did = this....

 

 

 

 

 

------=_NextPart_000_01DA_01CA20A7.FADF83E0--