Piper Flyer Association - Technical Know-how, Serious Fun read more

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    The Best Entry-Level Pipers

    Longtime Piper pilot and Piper twin owner Kristin Winter discusses the cream of the crop in entry-level Piper aircraft. (Photo: James Lawrence)

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    Short Wing Pipers

    Out of a poor economy came a series of aircraft that were better than expected. (Photo: Peter Lubig)

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    The Piper Navajo

    After initially feeling intimidated by the size of the Navajo, contributing editor Kristin Winter found that it really one of the easiest and most gentle aircraft she had flown. (Photo: Paul Bowen)

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  • "...nothing can replace the skill and confidence you get using spare training time to do weird things."

    - Kevin Garrison

  • "It costs fuel to carry fuel in any airplane..."

    -Thomas Block

  • "All of the PA-28-180/181 aircraft are great airplanes."

    - Kristin Winter

  •   "My happy place is metal and T-shaped and smells like 100 octane"

    - Kevin Garrison


replied to the topic 'Arrow 200 take off fuel flow' in the forum. 3 days ago

thanks very much for your opinion. I have a JPI EDM700 with fuel flow option and an OEM fuel flow gauge. They both match so I assume my JPI is set up correctly. My datalogs show about 15.8-16gph during take off and my hottest CHT never really exceeds 370 even in prolonged climbs to FL060-090.

I was just a little bit confused as to why all my cylinders peak EGT just about 50-75F leaner than full rich mixture.
So i see about 1450 on nr2 during take off.. it peaks at just about 1510. Same with other cylinders too. So it looks like sea level full mix full power runs just about 70F richer than peak egt. Everything I read on the internet points to full rich mix should be about 200-250F richer than peak EGT. That is why I thought my fuel flow was maybe not high enough.

But honestly, everything runs great. I just wanted to a 2nd opinion from here and got it!


STEVE ELLS replied to the topic 'Arrow 200 take off fuel flow' in the forum. 3 days ago

Hi Baris;
Great question. Let's take a look at some statistics about the systems involved.
I took a look at the Lycoming IO-360 Operators manual for some of this information.
Figure 3.5 in the manual cites a fuel consumption at 200 hp of 93.5 pounds per hour. 93.5 divided by 6 which represents the weight of a gallon of 100 LL avgas at average temperature yields a fuel power fuel flow of 15.58 gallons per hour.
Based on the data from the performance charts published by Lycoming, you are getting a little more than full power fuel flow at takeoff.
You quote a number of 16 gph fuel flow at takeoff. I'm going to assume that you're getting that number from a fuel flow gauge. If your fuel flow gauge is an aftermarket stand-alone gauge or is part of an aftermarket engine monitor such as the ones from Electronics International or JP Instruments, the fuel flow gph reading will be correct IF what's called the K-factor has been properly set during the installation of the gauge. You can verify the correctness of the K factor by filling your tanks to a recognizable spot on the filler neck, for instance. Then after taking off on one tank (we will call this tank 1) and climbing to altitude (any one you're comfortable with for leaning.) After leveling off, lean the engine in accordance with your normal practice at your normal cruise power setting. Then note the time and switch to the other fuel tank (tank 2). Fly without touching the throttle or mixture knobs or climbing or descending for an hour. Note the fuel flow gauge gph reading during the flight. At the end of exactly one hour, switch from tank 2 back to tank 1 and return to base. When fueling tank 2 the amount of the fill should match the fuel flow gauge gph setting. If it doesn't, you need to adjust the K-factor setting. It's usually pretty easy. Continue to adjust until you're within a few tenths of a gallon per hour.
Cylinder head temperatures (CHT) are the most important number during high power operations. EGT numbers are used to establish peak EGT when leaning at 75 percent or lower. Due to many variables such as installation orientation and distance from the cylinder exhaust flange, the actual numerical value of EGTs is not important.
If your CHT numbers stay below 400 during high power operations, you're getting sufficient fuel flow, no matter what your fuel flow gauge reads.
My suggestion is that you pay attention to your CHTs and do the K-factor calibration flight and adjust the K-factor if necessary.
Happy Flying


Jen D - updated event, 2018 Gathering at Waupaca 4 days ago