Differences in Mooney wings and control surfaces

[FloridaMan]

I've noticed that when I'm looking at other Mooneys that they seem to have different control surfaces. My 67F has a twisted wing and all of the control surfaces are smooth and seem like they have ribs inside of them. Others I've seen have control surfaces that look corrugated, like Cessna 172 control surfaces. Also, my 67F has a full-length rudder whereas a 67E model on the field's rudder only goes down to where the elevator is.

 

Could this smaller rudder have contributed to the reputation of Mooneys being easily upset in stalls, having little rudder authority and extreme difficulty in recovering from an upset? I know that the V-tail Bonanzas, even today, have a reputation for in-flight breakup in spite of the issue supposedly having been fixed early in the lifetime of the airplane. 

[Marauder]

I asked this question once (about the ribs versus non ribs ones). The reason for the ribbed versus non ribbed is due to the manufacturing process. The smooth ones have a series of ribs under the skin. The ribbed ones are riveted together at the depression area. Think lower manufacturing costs...

[KSMooniac]

Yep, the corrugated elevators are much easier to fabricate, and I believe they're stronger as well.  I think I read/understood that the yellow arc speed was increased after the elevators were switched to the corrugated configuration.  Unfortunately, it requires a big tool and press to fabricate the skins, and makes it harder to repair them in the field if they're significantly damaged.

[triple8s]

I had a discussion about this a few years ago with an engineer who was also a Mooney lover and he said he thought the smooth design was possibly a bit stronger because of internal stiffeners however they are a bit smaller. He also said one reason he thought the smooth was stronger was because of the size. I take this as being the opinion of an old engineer, key word being "opinion". I doubt seriously there is a huge difference in one design over the other, most vintage drivers I know frequent the yellow and orange arc region and how many inflight failures???? I'd bet the reason for the change is: manufacturing ease, and greater authority at slow speeds because of greater surface area, not because of strength. That is MY opinion. Seems like the more I learn about the Mooneys whether Vintage or later models its very clear they were way ahead of their time.

[jetdriven]

orange arc?

[triple8s]

yep

[triple8s]

Ya made me do a double take....My ASI is green up to 150 yellow from 150 to 170 and orange from there to Vne @ 190 (mph)

[Hank]

Hmmm . . . mine is green from I-forget-where to 175 mph, then yellow up to the redline at 200. And the trailing edges have large corrugations, about 1"or more wide and 5-6" in length, but the last 1/4" or so are pressed smoothly together, unlike Cessna's open diamonds on the trailing edge.

[FloridaMan]

67 E Rudder vs F (mine). Notice the E has a fixed tail cone, where mine is part of the rudder. 

[Marauder]

Hmmm...

[adrian]

Does anyone know what structural changes were made (if any) when Vne was increased on the M20E? It is annoyingly low in mine!

[Hank]

I'm not aware that any non-turbo M20-series planes have Vne> 200 mph. Although the later long-body models with Continental engines over 500 in3 may be different.

[triple8s]

hmmm so Hank's Vne is 10 mph higher than 880's? Oh well. hmmmm now I just looked at a pic of a 201 I had looked at trading for and its ASI has the yellow arc starting a 200 mph and he Vne is 225 mph. The tail on it was 201HV 1977 year model. The "O" has a Vne of 195kias with the yellow (no orange at all) begining at 175kias. I wonder why all differences when they all have such similar airframes?

[jetdriven]

M20J is 225 mph. Ours was in fact delivered with the 200 mph Vne and it was modified at the factory with the increased airspeed limits. It consisted of a new sidewall placard, remarked ASI, and a log entry.

[Bob_Belville]

My '66 E has rather low speed limitations:

Vno 150 (130k) (top of green)

Vne 189 (164k) red line

 

Cruise is routinely in the yellow,

500 fpm descent is close to the red line unless power id significantly reduced.

[Hank]

I knew flap and gear speeds varied a lot, but didn't realize red lines did too. The long bodies are built to go turbo fast, so it makes sense that the controls would be weighted and balanced for higher speed. But Js? I'm surprised.

500 fpm descent for me at 2500 is 170-175 mph, edge of the yellow. Maybe it's C-model drag, maybe it's the 3-blade speedbrake out front. First time I did that in an F, it put me 190-195 mph. But I also adjust throttle and mixture to maintain cruise values of MP & EGT.