Altitude selection

cowman

cowman

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This isn't an FAR question more of a preference question.

Say you're planning a flight that is going to take around 1hr. Conditions all along the route are sky clear and terrain is <1000' along that route. Winds are light at most altitudes and won't make a significant impact on your time enroute at any available altitude. There's no airspace of any note along the route either. No reports of turbulence or any airmets.

For simplicity's sake we'll say the direction of flight is westerly and you're flying a typical single engine unpressurized aircraft with no O2 and we're going to be going VFR. What altitude would you plan on using?
 
cowman said:
This isn't an FAR question more of a preference question.

Say you're planning a flight that is going to take around 1hr. Conditions all along the route are sky clear and terrain is <1000' along that route. Winds are light at most altitudes and won't make a significant impact on your time enroute at any available altitude. There's no airspace of any note along the route either. No reports of turbulence or any airmets.

For simplicity's sake we'll say the direction of flight is westerly and you're flying a typical single engine unpressurized aircraft with no O2 and we're going to be going VFR. What altitude would you plan on using?
Click to expand...

8500 or 10500 depending on the plane.

Altitude is life


Sent from my iPhone using Tapatalk
 
An hour is relatively short. Compelling reason to stay low is fuel cost to climb. Compelling reasons to go higher include glide distance, lower fuel burn at altitude, and airspace restrictions.

For me this question exclusively depends on terrain. If I am flying over airports and open fields lower would be cheaper and still reasonably safe. If I am flying over rolling hills without a lot of engine out options i would go higher.

In Ohio I commonly make this trip in the 5500 to 7500 range.
 
The maximum efficiency, no wind answer usually is to cruise-climb for half the flight then slow descend the second half. Just as sort of a practical approach to that I've used climb 1/3, cruise 1/3, descend 1/3 of trip time. It sorta works out. The actual benefit in terms of trip cost reduction is probably very small if winds are not a factor.
 
ChrisK said:
An hour is relatively short. Compelling reason to stay low is fuel cost to climb. Compelling reasons to go higher include glide distance, lower fuel burn at altitude, and airspace restrictions.

For me this question exclusively depends on terrain. If I am flying over airports and open fields lower would be cheaper and still reasonably safe. If I am flying over rolling hills without a lot of engine out options i would go higher.

In Ohio I commonly make this trip in the 5500 to 7500 range.
Click to expand...

In other words 6500 ft (OP said "westerly" & VFR). ;)
 
cowman said:
This isn't an FAR question more of a preference question.

Say you're planning a flight that is going to take around 1hr. Conditions all along the route are sky clear and terrain is <1000' along that route. Winds are light at most altitudes and won't make a significant impact on your time enroute at any available altitude. There's no airspace of any note along the route either. No reports of turbulence or any airmets.

For simplicity's sake we'll say the direction of flight is westerly and you're flying a typical single engine unpressurized aircraft with no O2 and we're going to be going VFR. What altitude would you plan on using?
Click to expand...

Depends on my mood. For traffic, bugs and bumps, I'd prefer 6500-8500. Sometimes it's just nice to stay down low and sight-see. I've done this at 1000 agl just because. Especially in your home state where there is always a flat farm field in gliding distance.
 
ChrisK said:
I could not offer an altitude for this scenario because it depends on terrain.
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I was just going by the OP's "<1000 ft" terrain specification.

But then the OP also said clear skies, light winds, no airmets, no turbulence, no airspace issues...which is about as fairy tale as it gets in this game. :D
The only thing missing to complete the fantasy is one dollar a gallon avgas. :rolleyes:
 
In your scenario I would very likely chose 6,500. We are in Michigan - no obsticals in any direction that I couldn’t pass... :D
 
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4500 or 6500
Depends a lot on type plane, C152/172 probably 4500, C182 higher. Same with other brand comparable models to these.

Breezy, Cub hmm maybe 1500/2000' agl, if that high.
 
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"Traffic! Traffic!"

No one is going with the Russ Paielli/Robert Patlovany altitudes yet?
(wiki navigation paradox for more information)
 
With low terrain, 5500 or 6500 are my defaults for 1hr ish flights over land, wx permitting
 
6500 & 7500 each direction. Best speed, most efficient for me. Plus I’m not goofed up by too much lack of O2 (may be all in my head).
 
cowman said:
This isn't an FAR question more of a preference question.

Say you're planning a flight that is going to take around 1hr. Conditions all along the route are sky clear and terrain is <1000' along that route. Winds are light at most altitudes and won't make a significant impact on your time enroute at any available altitude. There's no airspace of any note along the route either. No reports of turbulence or any airmets.

For simplicity's sake we'll say the direction of flight is westerly and you're flying a typical single engine unpressurized aircraft with no O2 and we're going to be going VFR. What altitude would you plan on using?
Click to expand...

6500 or 8500 ft in a non turbo charged single engine because that is the altitude for best cruise speed.
 
3,000 is my default for short flights. 7,500/8,500 for long flights, for the reason described above. 10,500/11,500 in a turbo. At least my former Turbo Arrow with non-pressurized mags.
 
6.5 or 8.5 for me as well. Most comfortable, decent altitude for safety, you're not climbing all day to get there, not too high to deal with potential O2 issues, etc. Same relative reasons the others have posted. For me (PA28-181) 10.5 is a bit too high unless there's a reason like winds, airspace or something to justify it.
 
I have a 2 hats with several pieces of paper with various altitudes written on them, I just pick an altitude that way. I have an east and a west hat.
 
I’ll echo the 6500 or 8500 comments for a different reason: it makes the LOP ops easier and safer. The red box starts to disappear at around that altitude.
 
I like 9500' or 10500' if I'm doing a two-hour flight. With a typical winds-aloft push from west to east, you can get some great ground speeds up higher.

On the way back, I might go lower if it means less headwind, so maybe 6500'.
 
MIFlyer said:
Altitude is life
Click to expand...
Yes!

I fly as high as reasonable. I think the view is better / cooler anyway.. and if the Conti give up the ghost I'll take every extra second I can
 
Your scenario describes a typical flight to Phoenix for me. 6,500' unless its bumpy then climb to 8,500...or not, it's only an hour.

But then again, I'm at 3,000' before I turn crosswind after take off.
 
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Tantalum said:
Yes!

I fly as high as reasonable. I think the view is better / cooler anyway.. and when the Conti gives up the ghost I'll have every extra second I can
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This Lycoming guy couldn't help but FTFY
 
I would probably select 8000' for my Piper Dakota. If it is a hot day, maybe 10,000' to find cooler air. I'd file IFR regardless of the weather conditions.
 
All things being equal I find myself crusing at 5500/6500 for one hour-ish flights. Longer I am higher
 
In the scenario given, I’d level off at 6500.
 
Let'sgoflying! said:
"Traffic! Traffic!"

No one is going with the Russ Paielli/Robert Patlovany altitudes yet?
(wiki navigation paradox for more information)
Click to expand...

After reading this I'm going to add a little "error" into my cruising altitudes.
15000.PNG
 
Here’s a way to view it graphically.

Cruise%20Performance%20Chart%20(True%20Airspeed),%20Langley%20Flying%20School.gif


Choose your desired power setting. See where it intercepts the Full Throttle line. That will give you the best speed and range for a given power setting.

For 75% power, it looks like about 7,500’. Any lower, you’ll be going slower for the same power setting.

For 65% power, it’s about 10,500’ and the same apples.

This is all things being equal.

1) For long legs, anything above 8,000’ or so tends to fatigue me without oxygen.

2) WINGXPRO7 has a button to “Optimize Altitude” based on current winds. It often makes it clear that staying low may avoid or minimize a headwind, or climbing higher will take advantage of a tailwind. I assume other flight planning software has a similar feature.

3) Over rough (or any) terrain, going higher gives you more gliding distance to an emergency landing site.

4) In the summertime, climbing to cooler air is often desirable.
 
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