188kts ground speed in an Arrow

mandm

mandm

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Michael
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Just flew Chicago to NYC yesterday with some serious tailwinds!

To be fair the 188kts GS was in a descent but averaged probably close to 180kts ground speed most of the way. (Don’t worry, well under red line)
 
I got 198 mph gs in my Archer going eastbound at altitude from Cincinnati to NY years ago. Happens occasionally but not often enough. Savor it.

BTW, it was severe clear the whole way in the winter.
 
Gotta love a good tailwind. Last month I hit 205 in my Decathlon. Had to climb to 10K to get it all. Montgomery AL to Tampa in 2:30 on the nose.
Unfortunately my GS was 105 going up there, and I was dodging radio towers at 1K AGL to stay under the stronger winds aloft.
 
My buddy bought a PA28R-200 a couple years ago. He had to wait 2 months to fly it home to Cincinnati from Duluth Mn because of the winter weather up there. I watched him fly it home on flightaware with a tail wind and he was hitting 200!
 
As you go up, your IAS reduces 2% per thousand feet right? So at 10k feet you are showing 20% less IAS. How does that come into play?
 
No, your TAS goes up by 2% per thousand feet. Your IAS goes down by the reduction in power, but you can maintain full cruise power up to around 7000 feet for normally aspirated.
 
Then how was I doing 188kts GS at 11.5k?
 
MY best ground speed in a 182 was 419 knots in reverse, according to Garmin Pilot. It then showed me doing a full 360 before getting back on course at normal ground speed.
 
mandm said:
Then how was I doing 188kts GS at 11.5k?
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120 knots IAS at sea level is 120 knots. 120 KIAS at 11.5K is 140 KTAS.

So you gain 20 knots. Add in a 44 knot tail wind component and you are at 188 GS.

On trip last summer I was at 135 KIAS, but a GS of 229 knots. I was at 17,000 (turbo) (175 KTAS) and a 54 knot tail wind.
 
Pinecone said:
120 knots IAS at sea level is 120 knots. 120 KIAS at 11.5K is 140 KTAS.

So you gain 20 knots. Add in a 44 knot tail wind component and you are at 188 GS.

On trip last summer I was at 135 KIAS, but a GS of 229 knots. I was at 17,000 (turbo) (175 KTAS) and a 54 knot tail wind.
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But I don't think a normally aspirated arrow (and this is a 180 hp arrow, correct) can do 140 ktas at 11.5k MSL. Am I wrong?
 
Tailwinds can result in serious ground speed. I remember a number of years ago riding an airliner back from Japan to the US when if our ground speed had been airspeed, we were supersonic. 200 mph on the tail will do that! Another time we got into SFO so early that we had to sit on the plane and wait for customs to open for the day. Tailwinds aren't always your friend. ;)
 
I topped Mandm’s Arrow by 1 kt in my Archer. Serious tailwind in the California desert.
 

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I just had post. You made me do it.
 

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