New K231

[Pritch]

I have a letter dated June 22 1984 to Mooney 231 owners from Leroy Lopresti.  "For a short field takeoff, I put in the cowl flaps in trail, or when I'm really pinched, close them for the takeoff run; they make a significant difference in the airplane's rate of climb. Be sure to open them again as soon as you have cleared whatever obstacle are in your path."  Interesting papers one finds in the collection of files that comes with the airplane.

Pritch

[carusoam]

15 minutes ago, Pritch said:

I have a letter dated June 22 1984 to Mooney 231 owners from Leroy Lopresti.  "For a short field takeoff, I put in the cowl flaps in trail, or when I'm really pinched, close them for the takeoff run; they make a significant difference in the airplane's rate of climb. Be sure to open them again as soon as you have cleared whatever obstacle are in your path."  Interesting papers one finds in the collection of files that comes with the airplane.

Pritch

Got a pic of that?

Expect that is true... if you have the skills of Mr. Lopresti flying...

But how many feet of difference would he get?

A dozen, 25,  50?

Its going to be similar to the margin of error and the buffer being added in...

 

So... There may be somebody that follows this procedure... to save a few feet.... 

Maybe they can share how many feet this shaves off the T/O roll...

And how much their FF is during the T/O....  very ROP, with lots of cooling that way...

Best regards,

-a-

[Pritch]

Here is the letter  @carusoam

scanroy.pdf

[Ron McBride]

At 8000 ft. Density altitude, will a 231 use much more runway to takeoff then sea level.  Yes a little for airspeed indicator error, but what about propellor efficiency? 
 

just curios. 
 

[Aerodon]

10 minutes ago, Ron McBride said:

At 8000 ft. Density altitude, will a 231 use much more runway to takeoff then sea level.  Yes a little for airspeed indicator error, but what about propellor efficiency? 
 

just curios. 
 

I quickly looked at the chart on a 252, and it could use 50% more runway at 8000'.  Think of it like this, the airplane needs to get to a certain IAS.  At 8000' the TAS will be higher.  Therefore the ground speed will be higher.  I learned to fly at 5500' elevation, and often saw 8000' density altitudes.  When I flew to sea level destinations, I could not believe how slow the landings felt, and had to pay attention and believe the airspeed indicator.

 

Aerodon

[carusoam]

@Pritch,

Thanks a ton for sharing the LoPresti Letter!

Those details sounded familiar, but couldn’t believe they would be written into a procedure that wouldn’t have been edited by a family of lawyers...

Nothing better than hearing how to operate a Mooney than listening to Mr. LoPresti and Mr. Kromer...

Reading their documents are easy... no time spent wondering if the writer knows what he is talking about...   

Thanks again,

-a-

[RJBrown]

On 4/17/2021 at 10:39 AM, Aerodon said:

 I learned to fly at 5500' elevation, and often saw 8000' density altitudes.  When I flew to sea level destinations, I could not believe how slow the landings felt, and had to pay attention and believe the airspeed indicator.

 

Aerodon

I learned to fly at Denver Centennial airport MSL 5880’ first flight to California was to Palomar right on the coast. Never knew a 182 could fly that slow. 

[CoffeeCan]

I am late to this party, sorry about that... but back to the OP, and a couple of excellent comments thereafter, I would suggest that picking up a new M20K and flying it home without getting a good bit of transition training first would be minor lunacy. Even for an experienced C pilot. The M20K isn’t harder to fly, stick-and-rudder wise, but you have to manage the engine/turbo while you do so... and in critical takeoff and landing operations, your workload can be very busy indeed.  Transition training will help with that tremendously. 

if you haven’t already done so, buy Mike Busch’s “Engines” book. Mike hammers on the concept that engine management is temperature management. Temperature management is not feasible unless you have an engine monitor that gives you CHT for each cylinder. As another person wrote earlier, run your engine ROP until you really understand the principles of leaning and temperature. Do NOT lean after run up or on climb. 
 

I haven’t seen an update yet... did you pick up your new bird? Keep us posted. 

[gsxrpilot]

20 minutes ago, CoffeeCan said:

I am late to this party, sorry about that... but back to the OP, and a couple of excellent comments thereafter, I would suggest that picking up a new M20K and flying it home without getting a good bit of transition training first would be minor lunacy. Even for an experienced C pilot. The M20K isn’t harder to fly, stick-and-rudder wise, but you have to manage the engine/turbo while you do so... and in critical takeoff and landing operations, your workload can be very busy indeed.  Transition training will help with that tremendously. 

Hi, I'm the lunatic . I took my 400 hours of M20C experience and bought a 252. My first flight in an M20K was the flight home to Texas from northern Ohio... solo... with the POH and other assorted manuals on the seat next to me. 

But seriously, transition training is valuable and certainly would have shortened the learning curve for me.

[jlunseth]

I was at the Mooney PPP this last weekend. A number of people asked what i lean to on takeoff and my answer was I don’t. (KSAF is at 6300). They seemed skeptical. i know a couple of of veteran 231 flyers who still think that is the best way to climb. My point is that the concept of engine management in a turbo is foreign to pilots used to flying an NA and everyone tends to revert to Na methods, which are entirely wrong for turbo engine management. The aerodynamics of flying the K are not that different or hard compared to, say, a J. Managing the throttle is not difficult either. it is getting your head around engine management where a pilot new to turbos needs to have some authentic help, and frankly I have flown with some veteran instructors that apply NA engine management also. Go to Paul,or someone like Paul who knows turbo engine management.

[jlunseth]

PS “Oversquare” is another concept that I suppose you could apply to NA ops, but it has no application at all to turbo ops. My turbo, for example, is at full power at around 37 inches of MAP, and the max RPM’s are 2700, so I am routinely “oversquare” - by routinely I mean every single takeoff and always at cruise. At cruise I am usually 2450 and 34” MAP. Throw “square” out the pilot window in a strong wind. The compression ratio of the turbo engine is lower than that of an NA engine, therefore higher MAPs with lower RPMs.

[gsxrpilot]

2 hours ago, jlunseth said:

I was at the Mooney PPP this last weekend. A number of people asked what i lean to on takeoff and my answer was I don’t. (KSAF is at 6300). They seemed skeptical. i know a couple of of veteran 231 flyers who still think that is the best way to climb. My point is that the concept of engine management in a turbo is foreign to pilots used to flying an NA and everyone tends to revert to Na methods, which are entirely wrong for turbo engine management. The aerodynamics of flying the K are not that different or hard compared to, say, a J. Managing the throttle is not difficult either. it is getting your head around engine management where a pilot new to turbos needs to have some authentic help, and frankly I have flown with some veteran instructors that apply NA engine management also. Go to Paul,or someone like Paul who knows turbo engine management.

And by Paul, he means @kortopates, not me  just incase that wasn't completely obvious!

I couldn't agree more. While I didn't have any transition training prior to flying my turbo Mooney home, there were countless conversations with @kortopates and @KLRDMD, and Brian Lloyd about how to fly turbos. I'd only owned the 252 for a few weeks before going to Ada, OK for the weekend, in person, APS class. 

I didn't see all that much difference in the flying part, takeoffs, and landing, between the M20K and the M20C. There are certainly differences but nothing an average pilot can't adapt to quickly. But the engine management is very different. And if you don't know, you don't know.

[geoffb]

Agree with the above.  Transition training for someone with several hundred hours of Mooney time seems unnecessary.  I went from E to K this winter and like Paul, my first flight was solo.  In fact, haven’t managed time to get my instructor friend in it.  Flying it is the same except for the added weight.  I actually think the K is easier to fly and much easier to land.

At least with the 262 conversion, if you fly it around at low-ish power, low altitude and the cowl flaps open, I don’t think you can hurt it.  And with mine, 120kt full power climb it runs cool.  But engine management in cruise, trying to find the combination of rpm, manifold, fuel, and cowl flaps that’s does what you’d like is still a work in progress for me.  I don’t have cht issues, in my case it’s TIT that’s driving my settings.

[Tx_Aggie]

Not trying to hijack the post, but in high(er) density altitude scenarios and hot OAT (35-40*) in my J, if I lean for takeoff I notice very high CHTs until I’m able to climb out and get some better airflow across the cylinders. Am I missing something? This particular instance was at Lubbock, TX in August - not the highest elevation airport but hot temperatures simulated much higher altitudes. Thanks

[CoffeeCan]

On 4/28/2021 at 4:19 PM, jlunseth said:

PS “Oversquare” is another concept that I suppose you could apply to NA ops, but it has no application at all to turbo ops. My turbo, for example, is at full power at around 37 inches of MAP, and the max RPM’s are 2700, so I am routinely “oversquare” - by routinely I mean every single takeoff and always at cruise. At cruise I am usually 2450 and 34” MAP. Throw “square” out the pilot window in a strong wind. The compression ratio of the turbo engine is lower than that of an NA engine, therefore higher MAPs with lower RPMs.

I fly with more or less the same settings in cruise, do the Big Pull to get LOP, and run consistently good CHT's and TIT's. Staying full rich on takeoff and climb keeps them well below the safety margins.

I will confess that despite my transition training (which for a non-Mooney guy, was a like trying to get a drink of water out of a firehose!) it took a bit of reading, talking to other turbo Mooney pilots, reading posts here on MS, and finally Mike Busch's books to get me where I feel comfortable and confident I'm getting the best performance out of my engine and doing it the least harm. 

[CoffeeCan]

5 hours ago, Tx_Aggie said:

Not trying to hijack the post, but in high(er) density altitude scenarios and hot OAT (35-40*) in my J, if I lean for takeoff I notice very high CHTs until I’m able to climb out and get some better airflow across the cylinders. Am I missing something? This particular instance was at Lubbock, TX in August - not the highest elevation airport but hot temperatures simulated much higher altitudes. Thanks

Not to sound like a broken record, but you really need to get Mike Busch's "Engines" book. Continental sets the CHT redline at 460 F, but as Mike points out, your engine's aluminum cylinder heads become highly stressed if you run CHT's above 400 F.  You won't "kill" your engine, but you'll reach overhaul time a lot faster if you run hot. Busch recommends a max of 380 F for regular operations, and gives good reasons for that. You need to either enrich your mixture or slow your climb rate to keep your CHT's in the safe temperature range. 

[CoffeeCan]

On 4/28/2021 at 5:11 PM, gsxrpilot said:

....While I didn't have any transition training prior to flying my turbo Mooney home, there were countless conversations with @kortopates and @KLRDMD, and Brian Lloyd about how to fly turbos. I'd only owned the 252 for a few weeks before going to Ada, OK for the weekend, in person, APS class. 

I didn't see all that much difference in the flying part, takeoffs, and landing, between the M20K and the M20C. There are certainly differences but nothing an average pilot can't adapt to quickly. But the engine management is very different. And if you don't know, you don't know.

Paul, no disrespect intended with my "minor lunacy" comment, and I get that a well-seasoned normally aspirated Mooney driver is probably gonna do fine transitioning to the turbo versions without much or even any dual received time. 

The fellas you've mentioned have been really helpful to me, as well.  Particularly Brian, who I suspect has forgotten more about 20K engine management than I will ever know. 

[gsxrpilot]

53 minutes ago, CoffeeCan said:

Paul, no disrespect intended with my "minor lunacy" comment, and I get that a well-seasoned normally aspirated Mooney driver is probably gonna do fine transitioning to the turbo versions without much or even any dual received time. 

None taken 

When I got home with my new-to-me M20K 252 turbo Mooney, I said the first thing I'm gonna do is get Brian to go fly with me and teach me proper engine management. We just never found ourselves in the same cockpit at the same time. And now 700 hours of turbo Mooney time later... well, I would still like an opportunity to have Brian fly my Mooney. There is plenty to learn and like you said, he's got a wealth of knowledge on the subject.

[jlunseth]

On 4/28/2021 at 5:11 PM, gsxrpilot said:

I'd only owned the 252 for a few weeks before going to Ada, OK for the weekend, in person, APS class.

Me too, I took the class, maybe Paul (gsxr) and I were there at the same time. It took me about a year to get it figured out and start flying LOP regularly, I couldn't get over the feeling the fuel knob was going to fall off. Seriously, the main problem I found, adapting the techniques they teach to the TSIO360, was that all those guys are Beech guys so their experience is with large bores and mostly NA engines. I wrote them a couple of times and they always wrote back, but they were not familiar with the 231 set up. It took some experimenting. Come to find out the engine loves to run LOP. As Paul K. always points out, you gotta do a lean test and if needed, get GAMI's which I already had, but with that done the engine really likes it.