What altitude, speed, throttle and mixture should I use for Cessna 172 to get maximum range, any other tips would be appreciated too
The height ceiling altitude of the 172, the most efficient mach, which varies by alot of factors, I recommend trying to fly away from the wind to get tailwind
Fly at 70 knots, lean your mixture, or 3000 ft or 2500 AGL.
I mostly fly 2 person on board with a small bag of a cargo but sometimes I get 3rd passenger.
Once I reach on cruise altitude I lower the mixture (45 or 50, if the weather is too hot 70-75) and fly up to 6 hours non-stop.
I cruise between 8000-9000 feet but Cessna is capable of flying at max 15,000 feet with oxygen supply (Cessna company recommends it as max ceeling at 14000 but it flies at 15000 as well)
Not sure how accurate you can be in infinite flight since I’ve only flown the 172 a few times, but it’s going to come down to a few things. First, youre going to want to get as high as possible to make use of increased true airspeed to increase your range. It’s also going to help with your fuel burn since you’ll be operating at a leaner mixture setting.
Looking at the C172S operating handbook, picking 2500 RPM as an example gives you a fuel burn of 9.5 gallons per hour at 4000 feet, but that same setting will get you 8.2 gallons per hour at 10000 feet (these figures get even lower as temperature increases). So higher is better for fuel burn.
A good question to ask is are you going for maximum range or maximum endurance? Because they are two different things, but both will be improved by using a lower power setting giving you a lower airspeed. 2500 RPM was the example I picked for comparison, but referring the operating handbook again, at 10000 feet you can get a fuel burn as low as 6.8 gallons per hour while still maintaining 97 knots true airspeed with 2300 RPM, and a fuel burn even lower than that as temperature increases.
But all of this doesn’t mean anything unless youre properly leaning which is what you are going to want to focus on. As you climb, air density decreases and you need to decrease the amount of fuel going to the engine correspondingly. This is accomplished by looking at the Exhaust Gas Temperature (EGT) gauge that is found on the engine information display on the left side of the MFD (this is where I’m not sure if infinite flight gives this data accurately). As you lean the mixture (less fuel) you will see the EGT rise to a point, and then start decreasing rapidly along with engine RPM starting to decrease. Peak EGT (the highest it value it reaches) is what you will be looking for to achieve maximum fuel economy giving you the best range possible. The other technique is 50 degrees less than the peak which is a bit less efficient but gives you maximum performance, so it depends on which one you are looking for on any given day. So basically, start leaning the mixture slowly, watch the RPMs and EGT rise, and then when you get to the point where they start to decrease, enrichen the mixture slightly back to the point where that drop off happened and that should be your most efficient mixture setting. For max efficiency, you should be doing that process every time you change altitude, more fuel down low, less fuel up high.
Thank you everyone