Boeing 737 MAX 8 Mini Performance Analysis
It’ll leave an A-10 for dead on takeoff without even using full power. It’ll do a flat spin rivaling the best the F-22 has to offer. It’ll make it from Sydney to Los Angeles on a single tank of fuel. What plane did you think of?
If you said 737 MAX, then congrats! You can read a title.
Welcome back to this mini-series that I do every time a new airliner drops. Today we’ll be looking at the 737 MAX 8 and its performance, especially with regards to the A321-200 and the 737-800.
Before we start, let’s address the elephant in the room. Or more accurately, let’s address the elephant missing from the room. As @Alpha1Aviator pointed out yesterday, the OEW of the MAX is too low. I can’t seem to find official figures, but this official Boeing source for the 737 NG claims 91,300 lbs OEW. We know the 737 MAX airframe is about 6,500 lbs heavier than the NG, so an empty MAX probably weighs close to 98,000 lbs. However, in Infinite Flight, it weighs a whole 17,000 pounds less which is equivalent to 1.3 African Bush elephants. The more you know!
As always (because I somehow always seem to be caught up in this), all of this topic is purely informational. I am not telling Infinite Flight what to fix, nor am I saying anything needs to be fixed. I do this to get information out there and because I find it interesting. Simple as that.
Fuel-Related Performance
When the A380 came out, it retained a very nice, logical fuel curve. In that analysis, I said at the end that “I was fully expecting another 777-200(LR), but I’m happy to say this is not that”. Well. Welcome to “that” (kind of).
Fuel Burn
| Fuel Capacity | Tested Speed | Game Fuel | MFR | MPR |
|---|---|---|---|---|
| 45,702 lbs / 20,730 kgs | M 0.79 | 9hr 33m / 4,350 nm | 15hr 01m / 6,900 nm | 11hr 27m / 5,220 nm |
Flight Profile (East): FL290 (100%-91%), FL310 (90%-71%), FL330 (70%-61%), FL370 (60%-21%), FL350* (20%-0%)
Flight Profile (West): FL300 (100%-81%), FL320 (80%-71%), FL340 (70%-0%)
Additional Comments: You’ll notice that there is a place in this fuel curve where you get lighter, and yet the more efficient altitude is obtained via a step descent instead of a step climb. I don’t believe I’ve ever seen this before. Although, realistically, if you sit at FL370 you’re only going to leak about 12 minutes worth of fuel from 20% to 0% load. Just do that.
This is certainly a peculiar fuel curve, but let’s take a look at what it means in the grand scheme of things.
Flight Time
Just a simple measurement derived from the data. Empty is just a full load of fuel and no care for reserves. Passengers is a full passenger load, no cargo, 5% contingency fuel and an hour of reserves.
How does the MAX fare? Really well. Almost too well. Here’s another fun fact: the new MAX can fly longer with passengers and reserves than a completely unladen 757-200. Here are a list of routes you can fly carrying 189 passengers (typical limit) and a completely full cargo bin.
- The longest (historic) IRL 737 NG route, SUMU-MPTO. You would need 68% of your tanks.
- The longest IRL 737 MAX 8 route, EFHK-GVBA. You would need 77% of your tanks.
- The longest IRL A321LR route, EKCH-KIAD. You would need 89% of your tanks.
- Any future A321XLR route. That’s because in this setup the MAX has a range of 4,850 nm while the XLR slots in at 4,700 nm.
If you don’t care about reserves, you can do a lot of the world’s longest routes. The Sydney to Los Angeles I mentioned wasn’t an exaggeration - I actually did it, on solo, no tailwinds. It took 14hr 37m and I landed with 860 lbs of fuel left which is about 18 minutes, so figure 14hr 55m total range (less than 1% error on my part, crazy how math works). Not too bad considering for the first half of my flight I had the low power mode 5x time compression instability which increased fuel burn slightly every couple minutes.
For what it’s worth, the MAX 8 burns about 20% less fuel than what SimBrief calculates.
Range
These aircraft all do about the same speed, but let’s take a look at range anyways.
That’s a lot of range! The A320-200 is probably the most realistic fuel curve in all of Infinite Flight so that should tell you a lot about these other planes.
Boeing claims (officially) on Section 3.2.2 in this document the range of the 737 MAX 8. If I loaded the 97,000 lb MAX up with the 200 passengers (34,000 pounds), the official range is 3,550 nm and if we don’t include the elephant and say the MAX weighs 81,000 lb + 34,000 lb in passengers it would be 3,950 nm. With the Infinite Flight measurements being 4,830 nm and 5,220 nm, it’s flying 36% and 32% further. For reference, the A320-200 sits at 2% more, the 737-800 at 36% more, and the 777-200(LR) at 60% more.
Note that if you want to see if you can complete a flight, use the other chart because this one doesn’t account for winds.
Takeoff Performance
I heard a lot of people yesterday claiming that the MAX is an overpowered bird on takeoff. On initial testing, it certainly feels that way. It can take off out of Saba with some margin and it will then proceed to gain airspeed up to almost 300 knots while climbing 10,000 FPM (this means it will handily outrun the Infinite Flight A-10 despite having a slightly worse power to weight). Let’s not draw conclusions too fast and put some numbers to it.
For this test, I tested every plane twice at standard temperature and at sea level. The first test, carrying a full passenger load flying 4 hours and the second, carrying a full passenger load flying its maximum flight time. For the MAX, the community guide released claims max permissible thrust is 95% N1 which I assume is from consultation with pilots. I was not able to locate a solid source online for any of these planes but having flown the Fenix and PMDG versions of these planes that seems like a reasonable standard and will ensure consistency. I will be using Flaps 1 on the A320 family and 5 on the 737 family, and a 15% standard safety margin will be added.
So yes, it takes off quick. Really quick. In fact, it has a similar takeoff distance loaded with passengers as the old C750 did empty, and both would be capable of traversing a 12 hour flight afterwards.
Takeoff distance is difficult to get tabs on objectively. Infinite Flight’s 737 MAX 8 this configuration embarking on a 4 hour flight weighs 133,000 lbs, and filling up the tanks brings it to 160,000 lbs. At sea level and 15 degrees, these equate to runway requirements of 4,100 feet and 6,800 feet, which means the Infinite Flight MAX 8 takes off 17% and 39% faster. Essentially, it seems like the heavier you are the more comparatively powerful the plane becomes. Realistically though, you probably won’t be loading up the tanks like this because the longest IRL MAX 8 flight is 8 hours, so this is a reasonable result in my opinion.
Climb Performance
Speaking of being an overpowered bird, let’s look at climb performance.
This test measures the average climb rate an aircraft can obtain at 95% N1 from FL100 to FL280 whilst adjusting VS to maintain their Mach Transition Speed.
There’s no IRL measurement for this so we can only draw conclusions between planes. This seems to go along with my previous conclusion that this plane is more weight invariant than some of these others. It’s especially impressive outclimbing the 737-800 by 700 FPM whilst flying an extra 2.5 hours and carrying 11 more people.
Conclusion
Overall, it’s interesting to take a look at how this aircraft stacks up performance wise. Certainly, while these numbers do paint some type of story, the grand idea is that nobody really cares about that and you should all just go enjoy your shiny new aircraft. See you back here when the NEO or whatever mystery aircraft comes out!
