X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Tue, 15 Dec 2009 08:41:11 -0500 Message-ID: X-Original-Return-Path: Received: from imr-ma06.mx.aol.com ([64.12.78.142] verified) by logan.com (CommuniGate Pro SMTP 5.3c3) with ESMTP id 4021346 for lml@lancaironline.net; Tue, 15 Dec 2009 07:07:35 -0500 Received-SPF: pass receiver=logan.com; client-ip=64.12.78.142; envelope-from=REHBINC@aol.com Received: from imo-da01.mx.aol.com (imo-da01.mx.aol.com [205.188.169.199]) by imr-ma06.mx.aol.com (8.14.1/8.14.1) with ESMTP id nBFC6ogM002783 for ; Tue, 15 Dec 2009 07:06:50 -0500 Received: from REHBINC@aol.com by imo-da01.mx.aol.com (mail_out_v42.5.) id q.bfb.6ee39f52 (34894) for ; Tue, 15 Dec 2009 07:06:45 -0500 (EST) Received: from smtprly-mb02.mx.aol.com (smtprly-mb02.mx.aol.com [64.12.207.149]) by cia-da01.mx.aol.com (v126.13) with ESMTP id MAILCIADA013-5c664b277bd2322; Tue, 15 Dec 2009 07:06:45 -0500 Received: from webmail-d066 (webmail-d066.sim.aol.com [205.188.59.131]) by smtprly-mb02.mx.aol.com (v127.6) with ESMTP id MAILSMTPRLYMB024-5c664b277bd2322; Tue, 15 Dec 2009 07:06:42 -0500 References: X-Original-To: lml@lancaironline.net Subject: Re: [LML] Re: Vne discussion X-Original-Date: Tue, 15 Dec 2009 07:06:42 -0500 X-AOL-IP: 172.16.10.39 In-Reply-To: X-MB-Message-Source: WebUI MIME-Version: 1.0 From: rehbinc@aol.com X-MB-Message-Type: User Content-Type: multipart/alternative; boundary="--------MB_8CC4B9632E95FC9_40A0_1E4BF_webmail-d066.sysops.aol.com" X-Mailer: AOL Webmail 29970-STANDARD Received: from 172.16.10.39 by webmail-d066.sysops.aol.com (205.188.59.131) with HTTP (WebMailUI); Tue, 15 Dec 2009 07:06:42 -0500 X-Original-Message-Id: <8CC4B9632D8B61B-40A0-F175@webmail-d066.sysops.aol.com> X-Spam-Flag:NO X-AOL-SENDER: REHBINC@aol.com ----------MB_8CC4B9632E95FC9_40A0_1E4BF_webmail-d066.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" If you really want to know the answer, you should ask Lance or the enginee= r(s) responsible for the analysis. Unless one is privy to the calculations= and testing done on the airframe, there is no way of providing you with= a credible answer to your question.=20 As has been stated already, there are numerous potential reasons for failu= re as speed is increased. One that I haven=C2=B4t seen mentioned is aerody= namic heating and this is a speed limit on at least one miltary jet as the= canopy melts above this speed. Another is wing wake inteference with the= horizontal stabilizer, which was an issue with the P38. This is typically= a mach related issue. The list is quite extensive, and while many of the= possible limiting factors may be unrealistic for the 300 or Legacy there= are still many that may be applicable. Without being familliar with the= analysis of these planes, it is impossible to know what the critical limi= ting factor was in the assigning Vne. While it may be pleasing to know the answer for accademic reasons, what el= se would you do with the information? Alter the structure to increase Vne?= Can you analize the modification to determine its effect(s) upon the othe= r parameters than the one you are trying to improve? In other words, will= your fix actually reduce Vne? This can get very deep very fast. Don=C2=B4t feed the worms, Rob -----Original Message----- From: Wolfgang To: lml@lancaironline.net Sent: Mon, Dec 14, 2009 7:18 pm Subject: [LML] Re: Vne discussion I'm having difficulty understanding why no one can give direct answers. I'm only looking for the various factors that are used to determine Vne. Flutter, canopy being sucked off, skin surface excess vibration . . . ? ?= ? . . . not the explecit calculations. Let's narow it down, what factors for the 300 series and Legacy ? =20 Wolfgang =20 From: "Robert Pastusek" Sender: Subject: RE: [LML] Re: Vne discussion Date: Sun, 13 Dec 2009 17:37:39 -0500 To: lml@lancaironline.net Wolfgang, As has been stated a number of times on this forum, the determination of= Vne is a very complex and multi-discipline task. Not to repeat what=E2=80= =99s been said many times, the several aero engineers that participate in= this forum have suggested that this subject is probably beyond a basic ae= ro engineering degree. You=E2=80=99re unlikely to find one of these people= willing to offer a =E2=80=9Cback of the hand=E2=80=9D quick solution. LOT= S of information on the internet about this subject, and some serious read= ing available. a couple of courses on aeronautical design and finite eleme= nt analysis will give you some idea of what you are looking for. Definitel= y beyond a simple posting on the LML, IMHO. Bob=20 From: Sky2high@aol.com Sender: Subject: Re: [LML] Re: Vne discussion Date: Sun, 13 Dec 2009 17:37:27 -0500 To: lml =20 Yes, there was extensive information published here about the Vne determin= ation. =20 Scott Krueger From: Sky2high@aol.com Sender: Subject: Re: [LML] Re: Vne discussion Date: Sun, 13 Dec 2009 17:37:27 -0500 To: lml =20 Yes, there was extensive information published here about the Vne determin= ation. =20 Scott Krueger So . . . am I to conclude that there's nobody on the list that can identif= y how Vne is determined ? With all the experience of posters on this list, I'm surprised to say the= least. Is this black magic art or is there some real formula/procedure ? All I've seen here so far is "is that meadured in IAS, TAS OR Mach ?" or= "what is the speed for xxx airframe ?". . . . but nothing about how the number comes to be. Wolfgang ----------MB_8CC4B9632E95FC9_40A0_1E4BF_webmail-d066.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset="utf-8"
If you really want to know the answer, you should ask Lance or the en= gineer(s) responsible for the analysis. Unless one is privy to the calcula= tions and testing done on the airframe, there is no way of providing you= with a credible answer to your question.
 
As has been stated already, there are numerous potential reasons for= failure as speed is increased. One that I haven=C2=B4t seen mentioned is&= nbsp;aerodynamic heating and this is a speed limit on at least one miltary= jet as the canopy melts above this speed. Another is wing wake inteferenc= e with the horizontal stabilizer, which was an issue with the P38. This is= typically a mach related issue. The list is quite extensive, and while ma= ny of the possible limiting factors may be unrealistic for the 300 or Lega= cy there are still many that may be applicable. Without being familliar wi= th the analysis of these planes, it is impossible to know what the critica= l limiting factor was in the assigning Vne.

While it may be pleasing to know the answer for accademic reasons, what el= se would you do with the information? Alter the structure to increase Vne?= Can you analize the modification to determine its effect(s) upon the othe= r parameters than the one you are trying to improve? In other words, will= your fix actually reduce Vne? This can get very deep very fast.
 
Don=C2=B4t feed the worms,
 
Rob
-----Original Message-----
From: Wolfgang <Wolfgang@MiCom.net>
To: lml@lancaironline.net
Sent: Mon, Dec 14, 2009 7:18 pm
Subject: [LML] Re: Vne discussion

I'm having difficulty understanding why no one can give direct answer= s.
I'm only looking for the various factors that are used to determine= Vne.
Flutter, canopy being sucked off, skin surface excess vibration . .= . ? ? ?
. . . not the explecit calculations.
Let's narow it down, what factors for the 300 series and Legacy ?
 
Wolfgang

 
From: "Robert Pastusek" <rpastusek@htii.com>
Sender: <ma= rv@lancaironline.net>
Subject: RE: [LML] Re: Vne discussion
Date: Sun, 13 Dec 2009 17:37:39 -0500
To: lml@lan= caironline.net
Wolfgang,
As has been stated a number of times on this= forum, the determination of Vne is a very complex and multi-discipline ta= sk. Not to repeat what=E2=80=99s been said many times, the several aero en= gineers that participate in this forum have suggested that this subject is= probably beyond a basic aero engineering degree. You=E2=80=99re unlikely= to find one of these people willing to offer a =E2=80=9Cback of the hand= =E2=80=9D quick solution. LOTS of information on the internet about this= subject, and some serious reading available. a couple of courses on aeron= autical design and finite element analysis will give you some idea of what= you are looking for. Definitely beyond a simple posting on the LML, IMHO.=
Bob=20
From: Sky2high@aol= .com
Sender: <ma= rv@lancaironline.net>
Subject: Re: [LML] Re: Vne discussion
Date: Sun, 13 Dec 2009 17:37:27 -0500
To: lml

 
Yes, there was extensive information published here about the Vne det= ermination.
 
Scott Krueger
So . . . am I to conclude that there's nobody= on the list that can identify how Vne is determined ?
With all the experience of posters on this li= st, I'm surprised to say the least.
Is this black magic art or is there some real= formula/procedure ?
All I've seen here so far is "is that meadure= d in IAS, TAS OR Mach ?" or "what is the speed for xxx airframe ?".
. . . but nothing about how the number comes= to be.
Wolfgang
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