Question - M20R Commercial Maneuvers Speeds and Settings

[gsengle]

Hey all - have a very specific question - and a quick search of the forums didn't come up with an answer.  Has anyone worked out the optimal power settings and speeds for the set of commercial maneuvers in an Ovation?

I'm going to finish up my commercial soon, and know that the right settings are key to making every maneuver easier - and haven't worked it out yet.  Has anyone already done this and would care to share their recommendations? Steep turns, chandelles, lazy eights and eights on pylons?

thanks in advance!

Greg

[MHemperly]

I'm not sure about the O. But what I did for mine was find out what power setting keeps you at maneuvering speed in level flight.

[jlunseth]

Hopefully someone who knows the O will chime in.  I have a 231 and its been awhile since I did my commercial, but here are a few things I remember that might help.  First, design maneuvering is a maximum for all your maneuvers.  Bust Vna and you bust the checkride.  So you need to use speeds for your maneuvers that won't get you in trouble with that.  The one I can think of is Lazy 8s, where you will lose and gain speed through the maneuver.  

8's on pylons is pretty simple.  The maneuver takes some practice, but the speed is formulaic.  You will need to find the pivotal altitude formula.  Then think about the fact that you need to be concerned with ground clearances.  I used 1,000 feet AGL because that eliminates any arguments about congested/noncongested areas.  If you fly the maneuver at 110 kts. the pivotal altitude is 1100.  I found that the "magic" speed is not always that magic, but it is close.  

Chandelles are a full power maneuver.

Steep turns I would pick a setting that gives you 100 kts. for the turn.  110 works also.

Lazy 8s are the tricky one and I am going to suggest you find a good, Mooney qualified instructor to help with that one.  As I recall, I used 110 kts as my starting speed, which gave me a slight (9 kt) cushion from design maneuvering.  The tricky part is that at the top it is not simply a matter of pushing the nose over.  If you do that, the airframe is so slick you will pick up speed with each 8, and you will bust your speed tolerance in one or two 8s (and you have to hold it for three).  You need to let the plane fall at the top of the maneuver, its pretty simple but you really need someone to show it to you who knows what they are doing.  

[StevenL757]

Greg, agree mainly with Lunseth.  I used 110KIAS for my reference, which we established in the brief.  Forget MP and RPM settings...go by airspeed and you'll have less to remember.  Again, depending on how much gas you carry (+weight of you and DPE), your Va will be higher or lower, so plan on adjusting this number accordingly.

The Ovation is just as smooth in all of these maneuvers as it is in any other phase of flight, so relax and let the aircraft do the work.  As Lunseth mentioned, your chandelle entry will be full-power.  Given the Ovation's power (especially with a 310HP-equipped aircraft), you'll find she will want to climb to the moon when you start the maneuver - this is normal.  Be sure to ease out the roll as you complete the maneuver.  I was "spoken to" about that in my ride when I rolled out too quickly at the top.

[jlunseth]

There was one thing I forgot to mention.  WIth the maneuvers where you fly a fixed power setting and a speed tolerance, and that would be the 8's on pylons, the steep turn, and the Lazy 8's, make whatever power setting you need in order to hit your reference speed, and then fly level for a bit before starting the maneuver.  The airframe has a way of picking up speed.  If you are in level flight and make a power setting to hit a speed, you will find a minute or two later that you are going 5-10 knots faster because the plane is accelerating.  If you get impatient and start the maneuver too soon, and you have a +/- 5 or 10 kt. margin, the airframe acceleration alone will cause a problem by the time the maneuver is over.

[Mooney time]

We have to do some of your maneuvers every six months with the FFA since we use our ovation on a 135 certificate.  I found most maneuvers work best on the ovation at 17" and 2300 rpm, full rich.  This gives you 125 kts, making steep turns a snap, and the simpler, the better.   One thing I've found during checkrides, you don't have to show off how fast the O is, just that you can master the maneuvers, and it's much easier at these speeds than anything faster.

 

[milotron]

Working on my Canadian Commercial very shortly. Anybody have advice for similar settings on a 252?  Slow speed maneuvers, etc.

[carusoam]

Welcome out in the open, Mooney Time!

Best regards,

-a-

[jlunseth]

Milotron, not quite sure which maneuvers you consider "slow speed."  Our aircraft will cruise all day with a TAS in the 170 even 180 range if at altitude, so by that measure all the commercial maneuvers are slow speed maneuvers.  Read what I said earlier about not busting design maneuvering.  Mine is 119 KIAS (I have a 231).  According to my Mooney PPP book yours is 118, but I believe there are different max gross weight versions of the 252 and they have different Vna's, so you must look it up in your manual.  Your power settings need to give you a cushion below that number so that you don't ever exceed it, which is a bust if you have an alert examiner.

I did my practice work mostly in the summer and then my checkride in the late fall (Nov.). I found that because of temp changes the settings I used varied by about an inch MP, and actually more if I were to compare a very hot summer day to a very cool fall day.  That said, I recall that 2400 RPM/s and 21" would give me about 100 and 22" about 110.  Those are good speeds for the steep turns, Lazy8's, and 8's on pylons.  As I said in an earlier post, always set the speed and give the aircraft a little time to hit speed or you will find it accelerating during the maneuver and you can bust speed tolerance.  The Lazy 8's are the maneuver where that is most critical because the airframe likes to gain speed with each "fall."

For the really slow stuff, slow flight, you will need to get the aircraft in the proper configuration and then power back to a "short approach" setting like 16" or even less, and let the airframe fall behind the power curve, then power up to maintain the speed just above stall that you are looking for.  Your final power setting may be in the 20-21" range, but your speed should be in the 60's for slow flight.  That is part of the lesson.  You are behind the power curve.

For many other slow maneuvers, steep spirals and power off 180's, you may have little or no power.  The speed to burn into your memory is best glide.  Know it backwards and forwards, and it varies depending on who is in the aircraft (gross weight).  Best glide has the advantage of being near (but not quite as high as) the 60 degree bank stall speed.  You can bank as far as 60 in a steep spiral as I recall, but if you do that at 70 knots you will instantly stall.  The 60 degree bank stall speed in my aircraft is 90 kias, and the best glide is in the 81-85 range (depending on G.W.), so best glide will mostly keep you out of trouble.  If you do get the stall horn, level the bank or lower the nose or both.

Edited March 11, 2017 by jlunseth

[milotron]

Thanks very much jlunseth, This is good info. Mine is a 231 with 252 upgrades, so something in the middle; your airframe speeds are about the same, just different engine settings. I need to go through the MAPA manual again.

Canadian CPL doesn't do the chandelles, but adds spins, and some slow (stall horn blaring ) steep turns. Spins will be in the clubs 172 thank you....  

When I did the transition training getting the plane to actually do a power off stall required full flaps, gear down, etc just to slow down enough and stay in the practice area. Did you need to do something similar for your work?  I suppose it is a matter of keeping the speed down for the training and check ride so we don't have to decelerate fro  160kts.

At slow speeds like this were your running full rich?  Full cowl flaps open I presume?

With all of the effort we pay to running leaner mixtures, keeping it rich for these specialized maneuvers is not likely to cause harm, but doesn't feel right! I am thinking of the precautionary landing and other slow work.

I note your comments on keeping speeds down and correct. I need to get these speeds sorted and the setup procedures in place so I can focus on getting the procedures correct and not spend all my effort and attention fusing around getting the engine setup. That aspect is somewhat simpler in the 172, but is nowhere near as stable as the mooney is, even at the lower speeds.

[gsxrpilot]

30 minutes ago, milotron said:

At slow speeds like this were your running full rich?  Full cowl flaps open I presume?

With all of the effort we pay to running leaner mixtures, keeping it rich for these specialized maneuvers is not likely to cause harm, but doesn't feel right! I am thinking of the precautionary landing and other slow work.

I've not started on these commercial maneuvers yet, but will very soon... BUT... I do a lot of formation flying in my 252 and I'm usually at 19" or 20" so that everyone, including the C's, G's, etc in the formation still have plenty of acceleration. We fly full rich and prop full forward the whole time. I've done this for a couple of hours at a time with no adverse effects or noticing any issues.

[milotron]

1 minute ago, gsxrpilot said:

I've not started on these commercial maneuvers yet, but will very soon... BUT... I do a lot of formation flying in my 252 and I'm usually at 19" or 20" so that everyone, including the C's, G's, etc in the formation still have plenty of acceleration. We fly full rich and prop full forward the whole time. I've done this for a couple of hours at a time with no adverse effects or noticing any issues.

Are still seeing 2700rpm at those manifold pressure settings?

[gsxrpilot]

2 minutes ago, milotron said:

Are still seeing 2700rpm at those manifold pressure settings?

Hmmmm... I'm not sure. Probably yes or close. We always run the prop full forward as there are maneuvers where I need full power for a short burst and need the prop in position for that. And there's no time to get the prop before throttle. So it's alway full in.

[jlunseth]

I was trained to do power off stalls in a landing configuration (gear down, flaps down).  Might be in the Practical Test Standard, don't remember.  I am sure you could probably get there, clean, at a dead idle, but I think they want to see you go through the "clean up" as part of the stall recovery.  

I did all the maneuvers with cowl flaps closed, except the chandelle which is a full power climb and therfore needs improved cooling.  

I don't remember exacly what I was doing about mixture, but I definitely was not running full rich.  I run lean of peak quite a bit more now than I did back then.  At reduced power settings it does not matter where you run the engine, you can lean it out, run it at peak, anything below 65% power and you can't hurt the engine no matter where you run it.  I just wouldn't run it full rich, that's very rich in the K's because of the way the fuel flows are set up.  The only time you should be full rich is at full power.  When you need to power up, like a stall recovery, just push both knobs in.  I would have the RPMs at 2700 for the stalls, I typically do that anyway when I land - bring the RPMs up full during the approach so I am set up for a go around if need be.  But if full rich works for you, the worst that can happen is the plugs getting fouled.