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Pitot tube cover

Ex Bonanza Bucko

Well Known Member
Has anyone come up with a trick way to protect that sharp and pesky little pitot tube? Yesterday I walked past it and put a hole in my arm....that will heal...but I don't wanna damage the little thing by doing that again.

(BTW: local Airport Bums have asked what that is and I them it's my 22 cal. machine gun) :)!

EBB:)
 
Best one I saw was a guy who put a yellow tennis ball over it!

I fabricated a little plastic thread cap over it, made a small hole in the tip, and tied a plastic Do Not Remove to the inlet plugs. Works well?.until it's off and you knock your arm against it!! :p
 
We fashioned a pitot blank from a standard aircraft hose blank with a 'remove before flight' key fob (since upgraded to a Red Bull 'Flying Bulls' version!). A small hole prevents pressure change problems.



Prime reason for it is to prevent things climbing in and blocking the pitot tube, secondary reason is to prevent blood loss.

A secondary method is to leave the tow bar attached. Now I am the number one advocate of removing tow bars before you let go of it but on the RV-12, it does help keep peoples skin away from the sharp end of an RV-12....
 
See the modifications sticky thread at the top of the RV12 forum. A couple of good ideas in there.
 
I put a 5/16" vinyl screw protector on my pitot tube. Hillman part 881039 from Lowes.
Not only does it protect the pitot tube, it also protects skin. The vinyl cap fits tightly.
I put a very small vent hole in the end of the vinyl cap to prevent stressing the Dynon pressure sensor.
The hole is big enough for light to shine through, but will keep all but the tiniest bugs out.
One time I forgot to remove the cap, but the airspeed indicator and AOA worked as normal.
Those functions depend on pressure, not airflow. If the airspeed works OK with the cap on, then why take it off?
So I have left the cap on for the last several flights with no apparent indication errors.
 
I used the rubber bulb off a Rogaine eye dropper with a REMOVE BEFORE FLIGHT key chain fob as a flag. I got way more usefulness out of it as a pitot cover than as a hair restorative!😝
 
If the airspeed works OK with the cap on, then why take it off?
So I have left the cap on for the last several flights with no apparent indication errors.

Interesting. Wouldn't the smaller hole be more prone to blockages in-flight though?
 
Has anyone come up with a trick way to protect that sharp and pesky little pitot tube? Yesterday I walked past it and put a hole in my arm....that will heal...but I don't wanna damage the little thing by doing that again.

(BTW: local Airport Bums have asked what that is and I them it's my 22 cal. machine gun) :)!

EBB:)

Van's Aircraft RV-12 Pitot Tube Cover w/ 12" Remove Before Flight Safety Streamer https://www.amazon.com/dp/B07W7PP7R5/ref=cm_sw_r_cp_api_glt_fabc_TH4HBEFDATVXTCXFEM2Q
 
During air show displays I typically install a pitot tube cover (a strip of brightly-colored cloth with a big knot in the middle of it that slips over the pitot tube) and a brightly-colored cloth streamer that clips onto the stall warning vane. Both of these covers are cheap and help prevent spectator injury.

ps -- Beware of tight-fitting pitot tube covers that tend to over-pressurize the pitot system when being installed.
 
I had a Searey that a bug decided to use as his home in the pitot tube. Didn’t see anything on preflight, but it became pretty obvious on the takeoff roll when airspeed didn’t come alive. What was worse was a pitot system leak on another hombuilt I had that gave airspeed alive, but it was reading about 10 knots low. Made me think I was close to stall on climb out.
 
I had IAS failure this week as I was approaching an out-lying airport. IAS went bonkers and showed a rapidly fluctuating 20-30 knots. I brought up a speedometer app on the iPad I use for foreflight which at least provided groundspeed for reference and headed for home. Landing without IAS was no problem. Full flaps and setting trim indicator 1/8” from top of scale always gives 55 knots hands-off.

After engine shutdown, a quick look showed pitot tube extended from front of spinner about 6”. Thinking that didn’t look right… I pulled the pitot tube straight out the front of the spinner. The aluminum tube fractured where threads begin at point where dimple is added to secure the tube from rotating in the nylon mounting block. I’m wondering if threads are “cut” or “rolled” during manufacture?

A new pitot tube is on order. I was able to repair the broken tube by inserting a hollow carbon fiber tube to “splint” the two broken sections. I had to open the aluminum tube ~ 0.010” for a nice slip fit and to allow super glue to wick into the joint. Repair is extremely strong and invisible to the eye.
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I use a tennis ball. Small slit in one side for the pitot tube, and I punched a couple of holes with an awl in the other side and attached a little "Remove before flight" keyring with an inch or two of safety wire. The streamer isn't really needed, I just had it laying around and used it. Easy to put on, easy to take off, and hard to lose. And it's bright yellow, so it even matches the airplane.
 
Jim, I had the same sheared pitot tube failure happen to me as I came into the pattern to land, but mine failed to zero. I have the old D180 and Garmin 396, so I just used the Garmin GS readout as a backup to the visual cues. I’m sure everybody had a CFI that at some point in their training made them shoot touch and goes with a covered Airspeed and Altimeter. Same thing with a “failed” landing light. If they didn’t they should get with a CFI and experience it.
 
I learned something about Super Glue. See post #16 above. Super Glue is Cyanoacrylate and has max operating temp of 180°F. I flew 45 minute flight with repaired (splint) pitot tube and it failed again. The joint slid apart because of heat from gearbox.

I am repairing once again while waiting for new pitot tube from Vans. This time using J-B Weld which will withstand a constant temperature of 500°F...
 
Jim, might not work for you, but mine sheared at a point that left enough length to reinstall the longest length and still penetrate the spinner bushing. Kept me flying until the replacement arrived.
 
Pitot cover

I cut off a short piece of 2x2, rounded one end, drilled a hole in the unrounded end the size of the pitot tube, painted it red, and hung a "Remove before flight" banner on it. I needed it because small children seem to have an undeniable urge to put mud into any open hole they find.
 
In post 7 above, I said that I left the vinyl cap (with a very small hole) on the pitot tube while flying. Airspeed seems to work OK, but AOA sounds the alarm at higher airspeeds. I no longer fly with the pitot tube cover on.
 
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