High Altitude Airports and LSA

Talk about airplanes! At last count, there are 39 (and growing) FAA certificated S-LSA (special light sport aircraft). These are factory-built ready to fly airplanes. If you can't afford a factory-built LSA, consider buying an E-LSA kit (experimental LSA - up to 99% complete).

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FlyAgain
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High Altitude Airports and LSA

Post by FlyAgain »

I'm considering pursuing a Light Sport endorsement, have PPL (haven't flown in ages) but don't want to play the medical game anymore. I live near Colorado Springs. We're at over 6,000 ft making density altitude a major issue as is the unpredictable winds we get here along the front range. A 75 degree day at Meadow Lake airport (KFLY) pushes the DA close to 10,000 ft. It doesn't seem LSA friendly. Does anyone own or operate LSAs in this kind of environment? There are some airports advertising LSA on the Front Range so it doesn't appear to be a showstopper but practically speaking how limiting is it? Thanks
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CharlieTango
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Re: High Altitude Airports and LSA

Post by CharlieTango »

My SLSA is, due to its great climb and speed far more capable then my 180hp skyhawk was.

Our field's on the Sierra front range @ 7,100'
TimTaylor
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Re: High Altitude Airports and LSA

Post by TimTaylor »

I'm not sure LSA would have anything to do with anything. All normally aspirated engines would sufffer the same loss in horsepower at altitude and every airplane has a maximum gross weight. The only difference with LSA is there is not as much potential weight reduction by leaving 3 passengers and lots of baggage behind. If you do a lot of flying by yourself, it would be a non-issue.
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FlyAgain
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Re: High Altitude Airports and LSA

Post by FlyAgain »

Thanks guys, good to know. Just now looking into this so thanks for the help. It would mostly just be me flying around.
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CharlieTango
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Re: High Altitude Airports and LSA

Post by CharlieTango »

TimTaylor wrote:I'm not sure LSA would have anything to do with anything. All normally aspirated engines would sufffer the same loss in horsepower at altitude and every airplane has a maximum gross weight. The only difference with LSA is there is not as much potential weight reduction by leaving 3 passengers and lots of baggage behind. If you do a lot of flying by yourself, it would be a non-issue.
100hp Rotax powered LSA are all 1,320lb MTOW which tends to mean they turn throttle into steep climb in a heartbeat. The constraints give it better clmib angle performance than many 4 passenger planes making it pretty well suited to high altitude ops. Even at 10,000' DA if I'm not flying in 5 seconds there is something wrong.

I often fly under 1,100lbs gross, that's ~ 20% reduction from max gross. Look at the work I do from my LSA, it says I have a lot of first hand experience. https://www.edcesnalis.com/
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Re: High Altitude Airports and LSA

Post by TimTaylor »

Not sure what that has to do with my post.
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FastEddieB
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Re: High Altitude Airports and LSA

Post by FastEddieB »

More than just the hp availabile, one needs to consider power/weight ratio.

A 100 hp LSA @ 1,320 lbs is very close to the same power/weight ratio as a Cirrus SR22 with 310 hp carrying 3,400 lbs.

Neither is a slouch, and both affected equally with increasing density altitude. But in either case, the POH will tell you what performance can be expected.
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CharlieTango
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Re: High Altitude Airports and LSA

Post by CharlieTango »

TimTaylor wrote:Not sure what that has to do with my post.
It counters 2 things you said
TimTaylor wrote:I'm not sure LSA would have anything to do with anything. All normally aspirated engines would sufffer the same loss in horsepower at altitude and every airplane has a maximum gross weight. The only difference with LSA is there is not as much potential weight reduction by leaving 3 passengers and lots of baggage behind. If you do a lot of flying by yourself, it would be a non-issue.
#1, actually you only said all NA engines suffer the same loss of power. Okay on a percentage basis that is true but the LSA like fast Eddie says is more like a Cirrus, more high performance on power / weight so better high altitude performance can be expected until you get to the power / weight of the mentioned /Cirrus.

#2 you have the LSA at a disadvantage due to not having 3 seats to leave empty but I countered that showing I get the big reduction as well. My LSA with passenger climbs better than my 180hp skyhawk did when solo.
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Re: High Altitude Airports and LSA

Post by TimTaylor »

I was looking at the Remos GX owner's manual earlier today (100 hp Rotax LSA) and in round numbers, the takeoff distance and over a 50 feet obstacle basically doubles at 10,000 feet vs sea level.
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Re: High Altitude Airports and LSA

Post by TimTaylor »

CharlieTango wrote:
TimTaylor wrote:Not sure what that has to do with my post.
It counters 2 things you said
TimTaylor wrote:I'm not sure LSA would have anything to do with anything. All normally aspirated engines would sufffer the same loss in horsepower at altitude and every airplane has a maximum gross weight. The only difference with LSA is there is not as much potential weight reduction by leaving 3 passengers and lots of baggage behind. If you do a lot of flying by yourself, it would be a non-issue.
#1, actually you only said all NA engines suffer the same loss of power. Okay on a percentage basis that is true but the LSA like fast Eddie says is more like a Cirrus, more high performance on power / weight so better high altitude performance can be expected until you get to the power / weight of the mentioned /Cirrus.

#2 you have the LSA at a disadvantage due to not having 3 seats to leave empty but I countered that showing I get the big reduction as well. My LSA with passenger climbs better than my 180hp skyhawk did when solo.
There is NOTHING resembling high performance with a 100 hp LSA. As FastEddie was pointing out, it has more to do with power to weight ratio than just power. Any yes, in an LSA, we can leave out one passenger and a little baggage and fuel to improve the power to weight ratio. In many other aircraft, you can leave out 3 or 5 passengers, lots of baggage, and lots of fuel to significantly improve power to weight ratio. You would have to do the arithmetic for each aircraft in question.

Why are some people here so defensive of their little LSA's? My point was, an LSA is fine flying at the altitudes the OP was asking about, and that's what I said.
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Type47
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Re: High Altitude Airports and LSA

Post by Type47 »

TimTaylor wrote:
CharlieTango wrote:
TimTaylor wrote:Not sure what that has to do with my post.
It counters 2 things you said
TimTaylor wrote:I'm not sure LSA would have anything to do with anything. All normally aspirated engines would sufffer the same loss in horsepower at altitude and every airplane has a maximum gross weight. The only difference with LSA is there is not as much potential weight reduction by leaving 3 passengers and lots of baggage behind. If you do a lot of flying by yourself, it would be a non-issue.
#1, actually you only said all NA engines suffer the same loss of power. Okay on a percentage basis that is true but the LSA like fast Eddie says is more like a Cirrus, more high performance on power / weight so better high altitude performance can be expected until you get to the power / weight of the mentioned /Cirrus.

#2 you have the LSA at a disadvantage due to not having 3 seats to leave empty but I countered that showing I get the big reduction as well. My LSA with passenger climbs better than my 180hp skyhawk did when solo.
There is NOTHING resembling high performance with a 100 hp LSA. As FastEddie was pointing out, it has more to do with power to weight ratio than just power. Any yes, in an LSA, we can leave out one passenger and a little baggage and fuel to improve the power to weight ratio. In many other aircraft, you can leave out 3 or 5 passengers, lots of baggage, and lots of fuel to significantly improve power to weight ratio. You would have to do the arithmetic for each aircraft in question.

Why are some people here so defensive of their little LSA's? My point was, an LSA is fine flying at the altitudes the OP was asking about, and that's what I said.
If I fly around in a Cessna 150 and then fly my Tecnam with the 100 hp Rotax, it sure feels high performance to me.
Maybe we are defensive of our “little” LSAs because we choose to fly them, love them, love being sport pilots and post on Sport Pilot Talk about them.
Perhaps there is a “I’d rather be flying a Mooney” site that would be a better fit for you?
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TimTaylor
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Re: High Altitude Airports and LSA

Post by TimTaylor »

FlyAgain wrote:I'm considering pursuing a Light Sport endorsement, have PPL (haven't flown in ages) but don't want to play the medical game anymore. I live near Colorado Springs. We're at over 6,000 ft making density altitude a major issue as is the unpredictable winds we get here along the front range. A 75 degree day at Meadow Lake airport (KFLY) pushes the DA close to 10,000 ft. It doesn't seem LSA friendly. Does anyone own or operate LSAs in this kind of environment? There are some airports advertising LSA on the Front Range so it doesn't appear to be a showstopper but practically speaking how limiting is it? Thanks
And just to reinforce, you'll be fine flying an LSA out there. There will be days you might rather be on the ground due to turbulence more than anything else.
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FastEddieB
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Re: High Altitude Airports and LSA

Post by FastEddieB »

That Aeroprakt A32 sure leapt off the ground in such a short distance that I’d consider it “high performance”.
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CharlieTango
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Re: High Altitude Airports and LSA

Post by CharlieTango »

TimTaylor wrote:There is NOTHING resembling high performance with a 100 hp LSA. As FastEddie was pointing out, it has more to do with power to weight ratio than just power. Any yes, in an LSA, we can leave out one passenger and a little baggage and fuel to improve the power to weight ratio. In many other aircraft, you can leave out 3 or 5 passengers, lots of baggage, and lots of fuel to significantly improve power to weight ratio. You would have to do the arithmetic for each aircraft in question.

Why are some people here so defensive of their little LSA's? My point was, an LSA is fine flying at the altitudes the OP was asking about, and that's what I said.
The question is about LSA opps at 10,000' DA. Light aircraft performance at that DA field elevation is about power / weight ratio more than anything. In the context of the question before us my LSA is high performance, I can see up to 1,000fpm climb at 10,000' DA where much of your 4 passenger fleet does less.

Your point is the LSA is fine, mine, after having operated out of a 7,1000' elevation field for 25 years is that its even preferable.
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CharlieTango
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Re: High Altitude Airports and LSA

Post by CharlieTango »

Another way a LSA can be preferable in a high altitude / front range field is its ability to use ridge lift, thermals and mountain wave for supplemental lift of even to power much of a flight.
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