X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Sat, 03 Nov 2007 19:04:24 -0400 Message-ID: X-Original-Return-Path: Received: from imo-d23.mx.aol.com ([205.188.139.137] verified) by logan.com (CommuniGate Pro SMTP 5.2c1) with ESMTP id 2453754 for lml@lancaironline.net; Sat, 03 Nov 2007 11:39:25 -0400 Received-SPF: pass receiver=logan.com; client-ip=205.188.139.137; envelope-from=Sky2high@aol.com Received: from Sky2high@aol.com by imo-d23.mx.aol.com (mail_out_v38_r9.3.) id q.bd1.1df486ee (39330) for ; Sat, 3 Nov 2007 11:38:43 -0400 (EDT) From: Sky2high@aol.com X-Original-Message-ID: X-Original-Date: Sat, 3 Nov 2007 11:38:43 EDT Subject: Re: [LML] beam spread table X-Original-To: lml@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="-----------------------------1194104323" X-Mailer: AOL 9.0 VR sub 5006 X-Spam-Flag: NO -------------------------------1194104323 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 11/3/2007 9:06:58 A.M. Central Daylight Time, colyncase@earthlink.net writes: If I did the math correctly, this is what you get from the 3 ansi designations for lights. beam spread (degrees) tan(beam spread) beam width at 100' (feet) beam width at 200' (feet) beam width at 300' (feet) beam width at 500' (feet) ideal taxi? 30 0.577 58 115 173 289 ideal landing? 10 0.176 18 35 53 88 eyf 12 0.213 21 43 64 106 eyj 25 0.466 47 93 140 233 eyc 40 0.839 84 168 252 420 Colyn, Since the beam forms an isosceles triangle your formula in column C should be 2*tan(radians(angle/2)). The widths are somewhat different for wider angle beams. I use a 12V 100W Halogen MR16 EMC (can't find the angle info) on the left leg for landing/taxiing and a GE quartz 12V 100W (Q4509?, 7 - 10 degree spread) cowling mounted lamp for approach/taxiing. The GE provides good lighting of the runway on approach but disappears from view on flare (can't see over the nose) and the leg light beautifully illuminates the area I can see down and to the left. I had pictures taken at night, but I can't find them at this time. Scott Krueger AKA Grayhawk Lancair N92EX IO320 SB 89/96 Aurora, IL (KARR) ************************************** See what's new at http://www.aol.com -------------------------------1194104323 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable
In a message dated 11/3/2007 9:06:58 A.M. Central Daylight Time,=20 colyncase@earthlink.net writes:
<= FONT=20 style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size= =3D2>
If I did the math correctly, this is what= you get=20 from the 3 ansi designations for lights.
 
  beam spread (degrees) tan(beam spread) beam width at 100' (feet) beam width at 200' (feet) beam width at 300' (feet) beam width at 500' (feet)
ideal taxi? 30 0.577 58 115 173 289
ideal landing? 10 0.176 18 35 53 88
eyf 12 0.213 21 43 64 106
eyj 25 0.466 47 93 140 233
eyc 40 0.839 84 168 252 420
 
 
Colyn,
 
Since the beam forms an isosceles triangle your formula in column C sho= uld=20 be 2*tan(radians(angle/2)).   The widths are somewhat=20 different for wider angle beams. 
 
I use a 12V 100W Halogen MR16 EMC (can't find the angle info) on t= he=20 left leg for landing/taxiing and a GE quartz 12V 100W (Q4509?, 7 -= 10=20 degree spread) cowling mounted lamp for approach/taxiing.  The GE provi= des=20 good lighting of the runway on approach but disappears from=20 view on flare (can't see over the nose) and the leg light=20 beautifully illuminates the area I can see down and to the left.&n= bsp;=20 I had pictures taken at night, but I can't find them at this=20 time.   =20
 
Scott Krueger=20 AKA Grayhawk
Lancair N92EX IO320 SB 89/96
Aurora, IL=20 (KARR)




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