Pitot Tube Bug Flap

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Robert Eilers
Posts: 652
Joined: Sat May 08, 2004 12:33 am

Pitot Tube Bug Flap

Post by Robert Eilers »

I have the original style pitot tube. Attached to it is a relative wind activated bug flap (for lack of a better description). The flap is closed when the is stopped and is opened by air force on a tab located above the flap. I noticed the other day that my pitot tube seemed lose. I checked inside the wing and found the pitot tube fastener in place. However it seems to me that the hard rubber grommet may be worn - most probably from the up force created on the pitot tube by the bug flap tab. Anyone have a similar device on their pitot tube? Any opinions regarding the value of the pitot bug flap?
"You have to learn how to fall before you learn how to fly"
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Bill Hart
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Re: Pitot Tube Bug Flap

Post by Bill Hart »

Could it just be a 60 year old grommet.
Robert Eilers
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Re: Pitot Tube Bug Flap

Post by Robert Eilers »

Speaking of grommets - where do you fidn these things? Don't see it in the parts manual.
"You have to learn how to fall before you learn how to fly"
voorheesh
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Joined: Tue Jan 04, 2005 5:22 am

Re: Pitot Tube Bug Flap

Post by voorheesh »

I have the bug flap on my 170A and have never given it much thought. There is supposedly a drawing or template you can use to make sure the pitot tube is in the right position (George will know about that). If you need a new grommet, I think you can "manufacture" one.
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GAHorn
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Re: Pitot Tube Bug Flap

Post by GAHorn »

You guys scare me sometimes.
Image

http://www.aircraftspruce.com/catalog/a ... metkit.php


The outline drawing for the pitot tube is found on page 16-9 (fig 16-3) of the 100 Series, 1962 and Prior Service Manual.
PitotOutline.JPG
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'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
Robert Eilers
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Joined: Sat May 08, 2004 12:33 am

Re: Pitot Tube Bug Flap

Post by Robert Eilers »

Thanks George - that is what I love about Aircraft Spruce, I have to buy 270 pieces to get the single grommet I want.
"You have to learn how to fall before you learn how to fly"
Chris Christensen
Posts: 51
Joined: Wed Dec 21, 2005 7:35 pm

Re: Pitot Tube Bug Flap

Post by Chris Christensen »

I may have several of them over at RHV if you can get over.
Let me know the Inside and Outside diameters.
Need an excuse to get out of the house.

PM me for a phone # or look up in 170 directory.

Brent, at AIRBOLT in Fresno will OFTEN sell you one of almost anything.

559-264-8900

He still shows up on Google search.

Also in Santa Clara is Motion Industries which will sell a lot less than 270
Ya will need to know the dimensions.

Chris C.
Palo Alto
53-170-B+
It is better to be late in this world, than early in the next !
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GAHorn
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Re: Pitot Tube Bug Flap

Post by GAHorn »

Robert Eilers wrote:Thanks George - that is what I love about Aircraft Spruce, I have to buy 270 pieces to get the single grommet I want.

Robert, go over to any NAPA autoparts store and tell them you want a rubber grommet for a 5/16" hole to hold a 1/4" tube. Probably cost you as much as twelve cents or so.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
N2625U
Posts: 188
Joined: Mon Jul 07, 2008 2:21 pm

Re: Pitot Tube Bug Flap

Post by N2625U »

Make sure you go to their 'Aviation Dept.'. :D
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GAHorn
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Re: Pitot Tube Bug Flap

Post by GAHorn »

By the way, the "Pitot Tube Bug Flap" ... is more commonly known as a "Pitot Tube Protector"

Image

The one most 170's uses is PN 10-02000, (the one on the right)

About $8 from : http://www.aircraftspruce.com/catalog/i ... tector.php
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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170C
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Joined: Tue May 06, 2003 11:59 am

Re: Pitot Tube Bug Flap

Post by 170C »

Those Pitot Tube Protectors/Bug Flaps work OK for bugs while sitting on the ramp (not tarmac), but it won't keep out those pesky little spiders that like to get in there and a part of their web will stick the flap to the tube. Sure brings home the reason to include checking the "protector"/flap" during preflight checks.
OLE POKEY
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N2255D
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Joined: Wed Apr 24, 2002 3:42 am

Re: Pitot Tube Bug Flap

Post by N2255D »

My C140 had one until I was working one windy day and it spent most of it's time in the "flying position". Didn't take a lot of wind to open it. I used a small rubber cap with streamer after that.
Walt Weaver
Spencer Airport (NC35)
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cessna170bdriver
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Re: Pitot Tube Bug Flap

Post by cessna170bdriver »

deleted by the author
Last edited by cessna170bdriver on Mon Aug 31, 2009 6:28 pm, edited 1 time in total.
Miles

“I envy no man that knows more than myself, but pity them that know less.”
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markeg1964
Posts: 66
Joined: Mon May 22, 2006 7:35 pm

Re: Pitot Tube Bug Flap

Post by markeg1964 »

During the first annual after getting my 170 the A&P removed my bug guard. When I asked him about it he said they cause more problems than they salve.
Mark

Twin Oaks Airpark
1950 170A N5528C
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bentley
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Joined: Thu Dec 11, 2003 5:49 pm

Re: Pitot Tube Bug Flap

Post by bentley »

Unless I execute one of my patented landings designed to calibrate the local university seismometer my bug flapper stays open even after shut down. I have often forgotten to check the thing following flight only to find it still in the open position days later (in the hangar). A slight finger bump will return it to closed but so far no amount of adjusting and applications of LPS seem to allow it to return closed following air movement. It is now simply an element of my post flight walk around to manually close the thing.
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