lml@lancaironline.net Mailing List Archive

Valin,

Here are pitot pressures as measured against a static source

Grayhawk

		Pressure in Units
IAS mph	Knots	"H2O	"Hg	PSI

40	34.8	0.79	0.06	0.028
50	43.4	1.23	0.09	0.044
60	52.1	1.77	0.13	0.064
70	60.8	2.41	0.18	0.087
80	69.5	3.15	0.23	0.114
90	78.2	4.00	0.29	0.144
100	86.9	4.94	0.36	0.178
110	95.6	5.98	0.44	0.216
120	104.3	7.12	0.52	0.257
130	113.0	8.37	0.62	0.302
140	121.7	9.72	0.71	0.351
150	130.3	11.17	0.82	0.403
160	139.0	12.72	0.94	0.460
170	147.7	14.39	1.06	0.520
180	156.4	16.15	1.19	0.583
190	165.1	18.03	1.33	0.651
200	173.8	20.01	1.47	0.722
210	182.5	22.10	1.62	0.798
220	191.2	24.29	1.79	0.877
230	199.9	26.60	1.96	0.961
240	208.6	29.03	2.13	1.048

In a message dated 5/30/2010 11:18:01 A.M. Central Daylight Time, thorn@starflight.aero writes:

Bruce,

Thanks for the link to the pressure switches. I’m looking at airspeed pressure switch options for possibly toggling in lower trim tab servo speeds at higher air speeds. I did a quick spreadsheet to see if the pressures for the switches at the link were in the needed range. If I did the calculations right, it looks like the lowest airspeed for the lowest pressure switch at that link (7.5-145 psi range) is for 100 kts.

Tom,

I can point you toward this 55 to 140 kts range airpseed switch offered by TCW Technologies – they make the Safety Trim product: http://www.tcwtech.com/usw-1.HTM You get the switch and relay for $95.

Hope this helps. Good luck,

Valin Thorn

Legacy project

Houston, TX USA

-----Original Message-----
From: Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf Of Bruce Gray
Sent: Sunday, May 30, 2010 8:54 AM
To: lml@lancaironline.net
Subject: [LML] Re: Low Pressure Gear Switch Needed

This is what I use for up/down pressure control on my GIII. It's an adjustable solid state pressure switch. Last one on the page.

http://www.automationdirect.com/adc/Search/Search?searchquery=psd25&cmd=Search&fctype=adc.falcon.search.SearchFormCtrl&TxnNumber=-1

Bruce

www.Glasair.org

-----Original Message-----

From: Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf Of

Tom McNerney

Sent: Sunday, May 30, 2010 1:09 AM

To: lml@lancaironline.net

Subject: [LML] Low Pressure Gear Switch Needed

I am helping with a new prototype that has a gear system similar to a

LNC2 or Legacy. We are trying to get it flying so we can make Oshkosh

this year. We recently ran into a bit of a holdup. The PS550 low

pressure switch for the landing gear system is on back order with

Lancair for at least 1 month. This would not leave us enough time to

test the gear system before the show. Does anybody know of an alternate

source for this pressure switch? Or, anybody have an extra to sell?

Rent? Loan for a month? :)

Thanks for your help.

Tom

dudewanarace@yahoo.com

www.N54SG.com

--

For archives and unsub

http://mail.lancaironline.net:81/lists/lml/List.html

--

For archives and unsub http://mail.lancaironline.net:81/lists/lml/List.html

image003.jpg

image004.jpg