Flying high in a non-turbo

[FloridaMan]

I know some of you guys fly higher than the 8-10,000 ft that I usually x/c at. What sort of efficiency and speed do you guys get up high? Is it worth getting O2 and going up above 14,000 for long trips? I've occasionally pushed up to 13,500 for weather and noticed that my Mooney has no trouble getting up that high with just me in it, though I can certainly feel the effects of the altitude. 

[co2bruce]

I fly xc at 11500-12500. I ended up getting o2, it's much more enjoyable. Arrive fresh with no headache. I have an Eagle and true airspeed is 176-180kts @ 14.5 gph

[carqwik]

I've found that the older I get (now mid-50s...omg), I need oxygen at lower altitudes than when I was younger.  Now, I always use O2 starting at 11,500 and higher...  You can get stupid with even slight oxygen deprivation...

[RobertE]

I routinely fly at 13K - 15K when crossing the Sierras or whatever those mountains by Salt Lake City are called (Wasatch??).  Sometimes I go to 17K to stay above the cumulus but the lazy way the aircraft responds up there creeps me out a bit.  I spent 2 hours at 15.5K yesterday where I noticed I was burning 7.5 GPH (lean of peak) with a true airspeed of 150 knots in a J.  I haven't done the math, but I bet whatever savings you get on fuel at that altitude you waste on oxygen.

[MooneyBob]

Ok. So it is reasonable altitude to fly 2.5 - 3 hours trip by the East Coast? Or better question is how do you determine your altitude for a trip ( not including the winds aloft calculations) ?

[co2bruce]

For a 3 hour trip, South Florida to North Carolina I fly 9-13 thousand depending on winds.

[Flymu2]

Ok. So it is reasonable altitude to fly 2.5 - 3 hours trip by the East Coast? Or better question is how do you determine your altitude for a trip ( not including the winds aloft calculations) ?

 

Depends where on the east coast. From DC to Boston IFR there's usually a single permitted altitude, usually 4-6000 ft. I even heard a G5 going from ACY to Leesburg at 5000. What a waste!

 

Generally, I find if you can get an accurate profile into fltplan.com, the winds aloft matrix is very accurate in predicting time and fuel burn. In my Eagle the differences have been 15 min and 1-3 gal from 5000 to the mid teens. The winds overwhelm any difference in performance.

[Flymu2]

I fly xc at 11500-12500. I ended up getting o2, it's much more enjoyable. Arrive fresh with no headache. I have an Eagle and true airspeed is 176-180kts @ 14.5 gph

 

Do you have the Screaming Eagle STC?

[flyboy0681]

For a 3 hour trip, South Florida to North Carolina I fly 9-13 thousand depending on winds.

 

Same here. I've been filing for 8-9k depending on winds. The best part of taking off from South Florida to these altitudes are the outside air temperatures, which hover around 60.

 

At those levels I'm burning the proverbial 10.5gph.

[FloridaMan]

FL to NC is 8-9k for me as well. I seem to see 11gph total, which makes sense with the initial climb. 

[Bob_Belville]

I added O2 a year or 2 ago. I use it a lot even though I seldom have good reason to go over 10,000. I'm sure it reduces fatigue. My A&P fills my tank gratis. I keep him in tomatoes.   

[Hank]

I've been crossing the Appalachians (WV, NC, TN, KY) routinely at 7-10K. Much above that my climb runs out of steam.

[cliffy]

Out here in the west I go as high as I need to to be cool first and smooth second. Most of the time in the summer I make the first but not the second. In the winter ice keeps me on the ground out here a lot of the time. My C gets iffy after 13,000 and so do I (no O2) Mostly 9 to 12,500. I use 10 gallons the first hour, 9 the second and 8 to 8.5 the third hour and on. I've done 5+ but now limit to 2 to 3 hr legs as I like to stop and smell the roses and I'm not in a hurry anymore.

[Oscar Avalle]

I regularly fly above 12k in my M20C. One thing to watch out is density altitude, in particular if you fly in areas where temperature is above normal. Density altitude may well be 1k or more higher than pressure altitude. This can become critical on take offs... 

 

I always try to use O2. It is amazing how much fresher you arrive compared to a flight without O2. 

 

A nice side effect is when you get a 45 mph tailwind (however most of the time you suffer it as a headwind) and suddenly your groundspeed becomes something to brag about! 

[Hank]

 

A nice side effect is when you get a 45 mph tailwind (however most of the time you suffer it as a headwind) and suddenly your groundspeed becomes something to brag about! 

 

Amen! I hit an all-time low groundspeed at 10K over the mountains NW of GSP, a whopping 68 knots. My wife said, "Sure am glad we aren't in a Cessna." 

[bonal]

What's the matter hank don't you like to fly backwards from time to time. 12500 seems fine in our DC 135K IAS is about normal at 2500rpm with the MP off an inch from max available. Me the wife full fuel and around 60lbs in the back.

[Hank]

What's the matter hank don't you like to fly backwards from time to time. 12500 seems fine in our DC 135K IAS is about normal at 2500rpm with the MP off an inch from max available. Me the wife full fuel and around 60lbs in the back.

 

That's about the load we had on that trip, and we were indicating around 135 mph at 2500 / 10,000 msl at sunset. The winds were howling that day--we made almost 120 knots at 4000, but had to climb for terrain; at 9000 we were right at 95 knots, but weaving between cloud tops at sunset [28ºF OAT] was getting old so I went over the clouds. Descended back to 9000 at 95 knots, then to 6000 at about 105. It was a long ride home . . . but headwinds happen. 

 

I generally back the throttle off the stops enough to make the MP needle move, whether it's a ½" or 1½". The higher I go, the further back I have to move it.

 

Most times, flying higher over mountains when the winds are strong will make for a smoother ride. Just try to fly with the wind and not into it. That's a flexibility that I don't always have, as I'm just a poor working stiff.

[bonal]

Amen brother the move from our 150 to the mooney has added a lot to our flying as much as I enjoyed the 150 my wife wanted something faster (lucky me). I'm not sure where the terrain back east would force a 9000 foot climb heck I got gofer mounds in my back yard taller than most of the hills east of the rocky's

[Hank]

There are ten? twenty? peaks along the TN/NC line over 6000 msl, with the tallest being Mt. Mitchell at 6800+. I always try to pass Mitchell on the upwind side, 20+ nm away. It carries a red CAUTION box on the Atlanta sectional warning of strong winds and turbulence. I've had mountain waves in the area take me up and down 200 feet while passing through on a North-South line at 10,000 msl. Hang on, I'll attach some photos after a while.

[N201MKTurbo]

I've had mountain waves in the area take me up and down 200 feet while passing through on a North-South line at 10,000 msl.

You flat lander easterners. You should try the Rockies some time!

Our mountain waves will send you up and down a few thousand feet.

[1964-M20E]

I generally fly 10k to 12k  for trips that are 2.5 hours or longer and for shorter trips 1 to 2.5 hours I generally fly between 6k and 8k.  The only times I fly lower are fun flights around town.

 

No O2 at the present time.

[Bartman]

We have taken our J up to 15,000 to avoid weather over the Appalachians. Climb was anemic the last couple thousand feet and the plane just felt twitchy in climb, almost like being close to stall but I know we were not. Cruise was fine and temps were good. Don't remember TAS.

I can confirm what Hank said. I have had bad experiences around Mt Mitchell. Flew thru a rotor there once in an otherwise crystal clear sky. Didn't realize what it was until the last minute and we were on IFR clearance. Now I know.

[Bob_Belville]

We have taken our J up to 15,000 to avoid weather over the Appalachians. Climb was anemic the last couple thousand feet and the plane just felt twitchy in climb, almost like being close to stall but I know we were not. Cruise was fine and temps were good. Don't remember TAS.

I can confirm what Hank said. I have had bad experiences around Mt Mitchell. Flew thru a rotor there once in an otherwise crystal clear sky. Didn't realize what it was until the last minute and we were on IFR clearance. Now I know.

Many years ago on a winter trip from PA to BNA  on the lee side of the Blue Ridge @ 8500' I could see Johnson City TN for 50 minutes. I didn't have the sense to turn 90 deg, cross the ridge, get in the updraft and gain about 75k.  

[aaronk25]

The plane flys the same at 110kts indicated at 15k as it does at 5k at 110kts indicated.

[Bartman]

The plane flys the same at 110kts indicated at 15k as it does at 5k at 110kts indicated.

I agree the plane flies the same at 110 indicated. Don't remember what the exact climb airspeed was but probably about 90 KIAS, but my J will not climb well at 110 KIAS at 15,000. Not even sure we read 110 in cruise at that altitude. May have been anxiety related to borderline hypoxia or maybe because the climb rate was so slow. Nonetheless it just felt like the plane was twitchy in climb the last couple thousand feet. That's my story and I'm sticking with it.

I also agree with oxygen even at lower altitudes. We feel a lot better at the destination when we use it.