X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Sun, 20 Dec 2009 22:38:19 -0500 Message-ID: X-Original-Return-Path: Received: from imr-db03.mx.aol.com ([205.188.91.97] verified) by logan.com (CommuniGate Pro SMTP 5.3c4) with ESMTP id 4032871 for lml@lancaironline.net; Sun, 20 Dec 2009 22:25:53 -0500 Received-SPF: pass receiver=logan.com; client-ip=205.188.91.97; envelope-from=Sky2high@aol.com Received: from imo-da02.mx.aol.com (imo-da02.mx.aol.com [205.188.169.200]) by imr-db03.mx.aol.com (8.14.1/8.14.1) with ESMTP id nBL3PF1d019018 for ; Sun, 20 Dec 2009 22:25:15 -0500 Received: from Sky2high@aol.com by imo-da02.mx.aol.com (mail_out_v42.5.) id q.d31.601deb34 (29672) for ; Sun, 20 Dec 2009 22:25:14 -0500 (EST) From: Sky2high@aol.com X-Original-Message-ID: X-Original-Date: Sun, 20 Dec 2009 22:26:29 EST Subject: Va X-Original-To: lml@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="-----------------------------1261365989" X-Mailer: AOL 9.5 sub 155 X-Spam-Flag:NO X-AOL-SENDER: Sky2high@aol.com -------------------------------1261365989 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Content-Language: en Topic changed so I changed the subject. =20 Generally, a Lancair 320 equipped with a 360 can easily push "cruise" into= =20 the yellow arc (> 180 KIAS) and stay there all day.. But to the point, = I=20 want to know how many have slowed their 320/360 to Va (143 KIAS) in =20 turbulence? Come on, raise your hands if you do that.... OK, I only see= 2 or 3=20 hands. =20 I have difficulty slowing down to 143 KIAS and I would use a few degrees= =20 of flaps to keep the nose down. I have slowed in nasty turbulence - to= =20 about 160 KIAS from 180. For me, nasty is my guess of moderate turbulenc= e as=20 evaluated in a 320.=20 =20 So, for those of us frequently flying in the yellow arc and not slowing to= =20 Va in turbulence, how are we different than Stuart's controlled expansion= =20 of the flight envelope beyond Vne? OK, that is from a structural aspect,= =20 not control surface flutter. =20 Well, let's see. Below Va is the speed at which no combination of =20 maneuver and gust load (<30 fps) at max gross weight cannot produce a pos= itive air=20 load that would create damage. =20 Va can be computed as Vs * SQRT(Limit load factor) =20 As originally set up, the stated limit was 4.5 Gs at 1685 pounds. And =20 let's say we use 68 KIAS as cruise configuration Vs (stall speed). =20 Then Va =3D 68* SQRT (4.5) =3D 68* 2.1 =3D 142.8 KIAS =20 =20 Grayhawk =20 =20 =20 =20 In a message dated 12/20/2009 6:35:13 P.M. Central Standard Time, =20 sltroutman@hotmail.com writes: It would seem to me that the maneuvering speed would be more of a concern= =20 than VNE but no mention of it yet. I bet that most have exceeded Va and= =20 never thought twice about it ??=20 ----- Original Message -----=20 From: _farnsworth_ (mailto:farnsworth@charter.net) =20 To: _lml@lancaironline.net_ (mailto:lml@lancaironline.net) =20 Sent: Sunday, December 20, 2009 6:51 AM Subject: [LML] Re: Tone on list =E2=80=9COn August 09, 2005 N750F, a Lancair IV-P disintegrated in flight= in a=20 dive at Mach 0.62. It is not in your list as it happened in Canada (Trans= port=20 Canada Report A05W0160). In June of 2003 N29ME, a Lancair IV-P, disintegrated in flight after=20 exceeding 253KTAS (274KIAS). (NTSB Report ATL03LA094)=E2=80=9D It appears that both accident aircraft were being flow in thunderstorms= at=20 the time they disintegrated.=20 Do you suppose that the turbulence associated with thunderstorms may have= =20 been a factor in these in-flight breakups?=20 Just wondering.=20 Lynn Farnsworth -------------------------------1261365989 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Content-Language: en
Topic changed so I changed the subject.
 
Generally, a Lancair 320 equipped with a 360 can easily push "cruise"= into=20 the yellow arc (> 180 KIAS) and stay there all day..  But to the= point,=20 I want to know how many have slowed their 320/360 to Va (143 KIAS) in=20 turbulence?  Come on, raise your hands if you do that.... OK, I= only=20 see 2 or 3 hands.
 
I have difficulty slowing down to 143 KIAS and I would use a few= =20 degrees of flaps to keep the nose down.  I have slowed in nasty turbu= lence=20 - to about 160 KIAS from 180.  For me, nasty is my guess of mode= rate=20 turbulence as evaluated in a 320. 
 
So, for those of us frequently flying in the yellow arc and not slowi= ng to=20 Va in turbulence, how are we different than Stuart's controlled expan= sion=20 of the flight envelope beyond Vne?  OK, that is from a structura= l=20 aspect, not control surface flutter.
 
Well, let's see.  Below Va is the speed at which no combination= of=20 maneuver and gust load (<30 fps) at max gross weight cannot produce a= =20 positive air load that would create damage.
 
Va can be computed as Vs * SQRT(Limit load factor)
 
As originally set up, the stated limit was 4.5 Gs at 1685 pounds.&nbs= p; And=20 let's say we use 68 KIAS as cruise configuration Vs (stall=20 speed).
 
Then Va =3D 68* SQRT (4.5) =3D 68* 2.1 =3D 142.8 KIAS
 
 
Grayhawk
 
 
 
In a message dated 12/20/2009 6:35:13 P.M. Central Standard Time,=20 sltroutman@hotmail.com writes:
It would seem to me that the maneuverin= g speed=20 would be more of a concern than VNE but no mention of it yet. I bet that= most=20 have exceeded Va and never thought twice about it ??
----- Original Message -----
= From:=20 farnsworth
To: lml@lancaironline.net
Sent: Sunday, December 20, 2009= 6:51=20 AM
Subject: [LML] Re: Tone on list=

 =

 =


=E2=80=9COn Aug= ust 09, 2005=20 N750F, a Lancair IV-P disintegrated in flight in a dive at Mach 0.62.= It is=20 not in your list as it happened in Canada (Transport Canada= Report=20 A05W0160).

In June of 2003 N29ME, a Lancair IV-P, disintegrated= in=20 flight after exceeding 253KTAS (274KIAS). (NTSB Report ATL03LA094)=E2=80=9D
It appears that both accident= aircraft=20 were being flow in thunderstorms at the time they=20 disintegrated.

Do=20 you suppose that the turbulence associated with thunderstorms may have= been=20 a factor in these in-flight breakups?

Just=20 wondering.

 =

Lynn=20 Farnsworth

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