Hello Guys and Gals

I am currently working alongside Rich at Checkmate Aviation trying to build a good checklist for our beloved birds. Initially, they won't have every model with all the engine/wing/prop/etc. variances but we're working on a standardized template that can easily be modified with the pertinent information and can even be customized to your liking.

I realize most of you have been flying your Maule for a while and probably have the checklists memorized and don't need one, but I have found my memory sometime formats its self without my permission so a checklist on-hand can take the guess work out of it. Also, It may help the future new Maule owners to give them a baseline to work from.

On to my real question:

Our Flight Manual / POH's state "Optimum Altitude" regarding fuel burn vs RPM vs Manifold Pressure.

Does anyone know of a documented "Optimum Altitude" for any or all of our models??

If not, What do you consider an "Optimum Altitude" for best performance/fuel burn/Ground speed/etc.

I understand the potential variables affecting this altitude number are probably endless and it will be somewhat different for every single aircraft. I'm just trying to get an idea of range and see if anyone has done any real world dynamic testing in search of this data.

Thanks!

I've wondered that myself. "Optimum". Hmmm...

On a standard day 'fastest' altitude is 7,500'.

Higher means less power, lower means more drag.

Just my math though, the Maule maunal not useful in the performance category.

Thanks M.D. for that info

You're correct, the Maule manual is fairly limited on performance data. I wonder if that is because they expected all of us to always be treetop level

I think its because they want to be able to shrug their shoulders and deny responsibility if we fail to clear treetop level...

Probably so, but thank goodness they gave us a wing that will clear the trees, almost all the time.

I have found around 7,500' is the optimum altitude for my airplane which falls in line with what Mountain Doc said. I have the O-540.

I rarely fly that high. Actually, I’ve only flown that high twice in my life, and once in the Maule. . I’ll certainly give that altitude a go on my next longer trip and see what the performance numbers shake out to be.

I’m usually cruising around 110mph at 2300 RPM or so at 3500 feet (about 2000 AGL around here in most places). Seem to recall on the O-360-C4F that’s a smidge under 65%.

If we didn't fly any higher than 7500', we'd smack into something that'd ruin our day

We've had the Maule anywhere from 500' to 12,500' so far. We still manage to squeeze 130 mph out of it in most of those altitudes. Since you gain about 2% airspeed for every 1000', I believe that the threshold where higher means slower is a little higher than 7500'. Even though your IAS decreases, your TAS is increasing to a point where the law of diminishing returns kicks in. Haven't calculated that out yet but I'm sure someone here has.

Chris in Milwaukee wrote:I rarely fly that high. Actually, I’ve only flown that high twice in my life, and once in the Maule. . I’ll certainly give that altitude a go on my next longer trip and see what the performance numbers shake out to be.

I’m usually cruising around 110mph at 2300 RPM or so at 3500 feet (about 2000 AGL around here in most places). Seem to recall on the O-360-C4F that’s a smidge under 65%.

I tend to cruise at 2500rpm, and I'm usually between 115-120mph. Recently I've been staying at 2500-4500 feet. When I bought it, I was at 9500 between PHX and ELP. 70 gallons gas, all my stuff, and then a bunch of extras with the plane had the weight way up...I may have been around 110mph for a while, but I think that was about the fastest that trip.

I don't get very involved with the speed or times and navlogs....I'll arrive when I arrive and stop for gas if it's needed. Usually guesstimate 100mph/kts and 10gph. Makes for easy math and anything better than that is a bonus in my mind!