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Highest density altitude takeoff in an E?


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I am planning on flying my 1970 E model to Jackson Hole, WY, and I’m a bit concerned about the takeoff afterwards. I’ll be about 250lbs under gross, at an OAT of about 60 degrees. Field elevatoon is 6450ft, and the runway is 6300ft. Can the E handle this?

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15 minutes ago, AndreiC said:

I am planning on flying my 1970 E model to Jackson Hole, WY, and I’m a bit concerned about the takeoff afterwards. I’ll be about 250lbs under gross, at an OAT of about 60 degrees. Field elevatoon is 6450ft, and the runway is 6300ft. Can the E handle this?

Do you have an operator's manual for your aircraft?  Does it list take off distances for DAs above 5K?  
 

This is the take off table for my 67F.  Should be very doable in a E, but does warrant consideration.

IMG_0217.jpeg.35a34d2fadf2ca664e986ed4300e3222.jpeg

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I took off from Carizzozo, NM last summer with a DA of 9k in my C. We were 400 below gross with a 5500ish foot runway. I took off about half way down and stayed in ground effect to the end of the runway to build speed, climb out was about 200FPM after I left ground effect. I had a big, wide valley to climb in and everything went as I expect/planned, it still gives you a little pucker though. I flew over towards the upwind side of the mountains surrounding the valley and caught an updraft that took my climb to 1500FPM.

If you've got a good plan and enough room to climb, you can make it work. You can go up in the airplane to a DA that matches what you expect at the field to determine what your climb performance is like. My 1963 Operator's Manual is pretty thin on stuff like that.

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Can’t say for an E, but I regularly flew a C out of KAPA (Denver), just under 6,000 msl, and flew in an out of KLVS (Las Vegas, NM), about 7,000 msl on warm days when the density altitude was significantly higher. 

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Assuming the book shows I can make the departure, I am far more concerned with the terrain/obstacles and wind after take off when dealing with a less than healthy rate of climb.

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This is a PIC decision, not really one for committee.
Without knowing this specific airplane or its condition, one can only give general advice.
I can say that this mission is well within the scope of operations for my M20F.

I can say the M20E is identical to my M20F save for 10” of fuselage. At 250lbs under his max gross of 2575lbs, his bird weighs 2325Lbs

I can say that at that weight under the conditions mentioned, I would expect my M20F to be airborne in under 2000’ and easily exceed 500fpm ROC through 10K.

That being said, over the years, I have collected a fair amount of repeatable, real world performance data on my specific airplane, so I know what it will do.

If plane and pilot are both healthy and current, this should be well within the aircraft’s performance envelope.
 

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22 hours ago, AndreiC said:

I am planning on flying my 1970 E model to Jackson Hole, WY, and I’m a bit concerned about the takeoff afterwards. I’ll be about 250lbs under gross, at an OAT of about 60 degrees. Field elevatoon is 6450ft, and the runway is 6300ft. Can the E handle this?

I have.

Been in and out of jackson many times.  the valley is very wide and long especially to the north. If you get turned to the north you will have lots of miles to gain altitude. 

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I flew out of Driggs Idaho in my G model yesterday which I think is at 6100 feet, the density altitude was over 7k and I climbed out just fine.   Jackson has a nice long runway and no immediate terrain you have to climb over which helps a lot.  
 

Given the 60 degree OAT and 250 under gross I think you’ll be fine.  Ultimately you are PIC and will have to make a decision based on all available information.  
 

If the conditions were 90 degree OAT and gross I would be a lot more concerned.   

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23 hours ago, AndreiC said:

I am planning on flying my 1970 E model to Jackson Hole, WY, and I’m a bit concerned about the takeoff afterwards. I’ll be about 250lbs under gross, at an OAT of about 60 degrees. Field elevatoon is 6450ft, and the runway is 6300ft. Can the E handle this?

You’ll be fine there. Couple of suggestions…. Make sure you fly in the morning when it’s cool and there’s less turbulence/winds around the mountains.  Have a good technique for leaning for takeoff and know how to use it (full power runup or target egt).  Lighter is better, so don’t take lots of extra gas (it’s $$ there anyway).  Climb out might be more interesting than takeoff.  You will climb out at a slower rate.  You’ll need to lean, but keep track of chts so you keep the engine happy.  ~120mph is still good.  Terrain is to the east and west.  Expect to climb for a whilst north/south before turning.

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My wife and I went to Yellowstone, we used Cody, WY, elevation 5100. Departure and climb to the north to go around the Sawtooth range in my C was easy, even though we were loaded up near gross; it was the week after Labor Day, and I'm pretty sure we were both in shorts. Since I only had about 200 hours total at the time, I passed on West Yellowstone.

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There is a lot of talk about the airplane doing just fine, and it will if you know how to fly it in those conditions but not much about the PIC. This FL based pilot would get a lesson in high DA operations and how to deal with mountains.

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9 hours ago, Paul Thomas said:

There is a lot of talk about the airplane doing just fine, and it will if you know how to fly it in those conditions but not much about the PIC. This FL based pilot would get a lesson in high DA operations and how to deal with mountains.

If it hasn’t already been said, this is important. Mountains aside, there have been nasty takeoff and landing accidents due to pilot failure to adapt their procedures to high density altitude conditions.

When I lived in Denver I used to get transients who wanted a lesson in high D-Alt ops or mountain flying. On takeoff one pulled the nose of a Skyhawk up to the pitch attitude they were used to at sea level. Not even aware of the airspeed bleeding off to a stall and, convinced it was perfect, refused to lower it when told. I had to manually push forward.

Then there was the one at the hold line in a fully loaded Cherokee who, cleared for takeoff, pushed the throttle forward and the engine quit because he hadn’t leaned for takeoff. Good thing that’s when it happened.

 

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41 minutes ago, midlifeflyer said:

If it hasn’t already been said, this is important. Mountains aside, there have been nasty takeoff and landing accidents due to pilot failure to adapt their procedures to high density altitude conditions.

When I lived in Denver I used to get transients who wanted a lesson in high D-Alt ops or mountain flying. On takeoff one pulled the nose of a Skyhawk up to the pitch attitude they were used to at sea level. Not even aware of the airspeed bleeding off to a stall and, convinced it was perfect, refused to lower it when told. I had to manually push forward.

Then there was the one at the hold line in a fully loaded Cherokee who, cleared for takeoff, pushed the throttle forward and the engine quit because he hadn’t leaned for takeoff. Good thing that’s when it happened.

The pilot needs to know how to adapt for high DA, but the OP's question was "is it possible for an E takeoff in these conditions," not "how can an E takeoff in these conditions."

That's a horse of another color!

Yes, the E can do it. No, it's not just like a sea-level takeoff.

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4 hours ago, Hank said:

The pilot needs to know how to adapt for high DA, but the OP's question was "is it possible for an E takeoff in these conditions," not "how can an E takeoff in these conditions."

That's a horse of another color!

Yes, the E can do it. No, it's not just like a sea-level takeoff.

Agreed. That original question appears to have been adequately answered several times. The rest is normal Internet thread drift.

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While yes taking off from that high of DA is absolutely possible, check your POH and be familiar with proper leaning for high altitude takeoffs. Make sure YOU can do it.

Look at the surrounding areas and leave plenty of outs.

I have taken off out of Durango(DRO) a number of times at full gross in my C with 10k+ ft DA in the summer. It is plenty capable but knowing how to properly lean and shallow the climb is very important. 

I came out of LXV with 11k DA no issues but its basically a huge valley to drop into for many many miles if you can't climb quickly. 

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OK, as the OP I feel obliged to respond to some of the comments. In the end I had to go to Driggs -- I was not aware of the fact that Jackson Hole has extremely limited overnight parking, which must be reserved well ahead of time. (They said 5 tie-down spots total.) Takeoff from Driggs was absolutely a non-issue. Much easier than a takeoff I did years ago from Fremont County (1V6) in a fully loaded Piper Cherokee 180 on a hot (90+ degrees F) day. 1V6 stands at 5450 feet.

My POH only shows information for 5000 pressure altitude and 80 degrees F. But @Shadrach's table for an F helped. Thanks to all who responded.

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On 6/3/2024 at 12:34 PM, AndreiC said:

OK, as the OP I feel obliged to respond to some of the comments. In the end I had to go to Driggs -- I was not aware of the fact that Jackson Hole has extremely limited overnight parking, which must be reserved well ahead of time. (They said 5 tie-down spots total.) Takeoff from Driggs was absolutely a non-issue. Much easier than a takeoff I did years ago from Fremont County (1V6) in a fully loaded Piper Cherokee 180 on a hot (90+ degrees F) day. 1V6 stands at 5450 feet.

My POH only shows information for 5000 pressure altitude and 80 degrees F. But @Shadrach's table for an F helped. Thanks to all who responded.

You should have opened with the limitations of your POH! I knew that some of the early owner's manuals are limited.  Stopping at 5000' just is not sufficient for planning. We have airports here in Maryland that see DAs in that range in the summer time.  Performance data can be interpolated, but it would be preferable in the event of an inquiry to have factory numbers to show as a reference.  

The truth is that a well sorted M20E is probably the best of the fleet for departing in the conditions that you have described. You're flying a light airframe that will be making >80% horsepower.  I can't imagine anything other Mooney besting your E's runway performance with a 700lb payload.

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31 minutes ago, Shadrach said:

You should have opened with the limitations of your POH! I knew that some of the early owner's manuals are limited.  Stopping at 5000' just is not sufficient for planning. We have airports here in Maryland that see DAs in that range in the summer time.  Performance data can be interpolated, but it would be preferable in the event of an inquiry to have factory numbers to show as a reference.  

The truth is that a well sorted M20E is probably the best of the fleet for departing in the conditions that you have described. You're flying a light airframe that will be making >80% horsepower.  I can't imagine anything other Mooney's besting your E's runway performance with a 700lb payload.

The koch chart can also help where poh data doesn’t exist.  This faa pamphlet is actually pretty useful:

https://www.faasafety.gov/files/events/nm/nm09/2013/nm0951144/density_altitude.pdf

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