Air Speed Question

[Diesel Dave]

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Finally have the Super Colt flying. Works great, completely surprised at her performance as was my check out instructor. 17 hours on the motor and all is well. I do wonder about my air speed though. It's been tough keeping power up for break-in and not over speeding. Channel chrome paranoid. The pic is 2300rpm, 130MPH IAS. It was cold out. -20C at the time. The motors an 0-320 A2B with a 74-DM6-0-58. It climbs at 1600-1700 Ft/Min. Crazy compared to anything else I've flown(150&172). Can't say what RPM it'll get too cause I run out of air speed indicator. Are these normal numbers? Will she slow down when the heat comes? Or is a re-pitched required? If I want to go slow and sight see I've got the carb heat pulled. 90MPH at 1600RPM. Pitot static test checked out. Verified the tach. The prop is a fresh overhaul as well. Afraid if I pitch anymore I'll have to bring the wee colt to the Kennedy Space Center for launch. 8000Hrs experience building and only 17 flying it so I don't know. 1582LBS takeoff weight
Thanks
Dave Hendriks

[Diesel Dave]

Also forgot to mention, Thank you to all who helped make it happen. Those who know who you are and many more through posts on the site. Great Info.
Thanks Again.
Dave
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[PACERGUY]

Is the airspeed matching the gps speed in a no wind condition? Shortenings are fast especially with little tires. DENNY

[Diesel Dave]

We did check at one point but never recorded it. I'd have to check, but ground speed is slower for sure. Top of my head GPS was 20MPH slower.

[Subsonic]

I think your airspeed indicator may be optimistic if you believe your RPM. Maybe 12 - 15 mph fast at that rpm. Mine indicated fast until I rebuilt my static system and swapped out the ASI for a newer rebuilt unit. Mechanical Tachometers can be off too. I went to digital tach for truth in the universe. If you were indicating 130 mph at 2600 rpm in a Colt, I'd believe it with a new 58" prop. Compare your landing speeds from ASI and GPS. They should be nearly identical. You can also do the triangle run at altitude compared to GPS ground speed and see what you get.

[walt.buskey]

Ah yes, the little town with the cool bridge-- glad you've got it in the air, congratulations!!

Mine's getting close (been saying that for a year or two at least) but I think this time for real.

[Steve Pierce]

Is your static hook up to the ports on the belly? Fly a 3 point GPS course 90 degrees to each other, record the ground speed and average them for your actual speed.

[Subsonic]

Is your static hook up to the ports on the belly? Fly a 3 point GPS course 90 degrees to each other, record the ground speed and average them for your actual speed.

90 degrees would require 4 points.

[Steve Pierce]

90 degrees would require 4 points.

That is what I do but someone told me you only needed to go 3 point. Didn't make sense at the time but I believed them.

[Gilbert Pierce]

If your static system is open behind the the panel your indicated airspeed will be 10 to 15 mph high. Looking at your power setting, air speed and 58” prop your airspeed indication is highly suspect. At 2300 rpm, 2000’ in my light weight Clipper, 160 hp, 58” prop I would be indicating about 105 to 110. I have a static system and calibrated it by flying a 4 course gps and doing the math to cancel out the wind.
According to the Lycoming power chart you are only making about 60% power.

Clippers and Vags were delivered without static ports. Several weeks ago I discovered a TriPacer with the static line open behind the panel. Suspect the avionics shop doing an IFR transponder check left it open when they reinstalled the altimeter.