M-7-235 or MX-7-180B

[Hogy59]

Okay Tribe!

I've had my MX-7-180B (long wing) about 15 years. I'm very satisfied with it...got about 1800 hours in it.....but the opportunity has come up to move to a newer M-7-235. I've never flown the M-7, so I'm looking for advice here.

To start off with, the M-7 I'm looking at is about 300# heavier on the empty weight. The difference in useful load really isn't a factor for me, since there are usually only 2 of us in the plane. I'm just wondering about the performance difference between a 300# lighter MX-7 vs the M-7.

Second question is handling....I've heard from this forum and others places that the MX-7-180 is better balanced than the M-7, i.e. less nose heavy. Even in the MX-7, I keep a junk box behind the back seat, and it is noticeable when it isn't there..(trim all the way nose up).

And I know this has been discussed, but Oleo gear on the MX-7 vs Spring gear on the M-7.

Some of you that have flown both pipe up here and let me know what you think....I live in the SE US, so high altitude performance isn't too much of a factor (unless I can talk Momma into going to Idaho for the summer!!!!)

Thanks

[andy]

The biggest difference that I've noticed is climb performance. The M-7 will out-climb the MX-7 especially if both airplanes are heavy or in high density altitude conditions - like Idaho. You can land the MX-7-180 slightly shorter than the M-7-235 due to lighter weight but it has more to do with technique. Takeoff distance is about the same unless you load the MX-7 up to max gross. It depends on the prop but the higher power M-7 accelerates faster thus shortening the takeoff. There are more prop choices for the O-540 than the O-360. The dry weight of an O-360 is about 289 lbs vs. 438 lbs for the O-540. Having more weight on the nose means that you have to be more careful not to apply the brakes too hard and nose over on landing. Counterbalancing the nose weight with more aft weight reduces the problem but reduces useful load. I don't think there is much difference in handling between the two in flight. At comparable loads of fuel, occupants and baggage, the M-7 is heavier than the MX-7 because of the engine. Being a heavier airplane means that the M-7 will sink faster at slow landing speeds than the MX-7 but that depends on the total weight. Both of them have a 2500 lb max gross weight. It's easier to lighten up a MX-7 than a M-7. Many owners who operate out of short airstrips or high density altitudes, lighten their airplanes as much as possible to improve performance.

It costs more to overhaul or buy a new or replacement engine for the O-540 than the O-360.

The M-7 has more headroom in the back seat than the MX-7 because of the way the tubing is constructed. That makes a difference if you have a tall rear seat passenger.

I haven't flown a Maule with spring aluminum gear but I've talked to owners. Many of them say that it's less forgiving than the oleo gear on rough airstrips and easier to bounce on landing but more stable due to the wider stance. Oleo gear is lighter than spring aluminum gear. My preference is oleo gear to take up more shock on rough back country airstrips.

It will cost more to buy a M-7 than a MX-7. How much more depends on the airplane, modifications, engine time, avionics, etc. Since the O-540 is over 200 hp, you need a high performance endorsement from a CFI. That's usually not much of an issue.

If you mostly fly with heavier weight or in higher density altitude conditions, the M-7 is a better choice due to its superior climb performance. A fuel injected IO-540 has better climb performance at high density altitude than a carbureted O-540. Even in the SE US density altitude can be a factor in the summer but unless you operate out of very short airstrips (less than 1000 ft) the MX-7 would work fine for two people and baggage.

[Hogy59]

Thanks Andy!!