Max altitude for a non-turbo M20F

[David Lloyd]

Engineer types.  Ratios and speeds in their head.  And the boss.  Okay, plenty of creative math there.

[Shadrach]

1 hour ago, David Lloyd said:

With unsuspecting passengers after an hour or so at 8 or 9000' I would hand them a notepad and ask them to add the numbers on it.  Simple stuff like 23+11+42.  Never got a correct answer. 

I would have guessed that these folks would have had to put some thought into these computations at sea level. I often fly above 10K and have no trouble calculating reciprocal headings,  on course heading or descent start to arrive at a specified altitude at a specified distance from the airport.  I'm not saying that my cognitive function doesn't degrade with altitude, but it's barely perceptible if at all at 8-9000.  I'm a flatlander who lives close enough to SL as to make no difference. I've never sensed degradation while staying in Telluride, CO (8750')  where O2 is about 70% of what it is at sea level.  Pikes Peak is a different story  at 58%.  On one visit to PP with a family member, I had to walk with her arm in arm to ensure she stayed upright.  I'd be a one beer drunk at 14,000'.

Edited August 28, 2018 by Shadrach

[gsxrpilot]

O2 debt affects different people differently. Fitness level and even age have much less to do with it than you would think. Both my brother and I seem to function pretty good up high, but I've had passengers that couldn't talk right past 18K. 

Cruising at FL200 with another pilot, we tested the effect of taking the mask off while the other pilot flew the plane. The difference between the two of us was night and day.

[Guest]

4 hours ago, aviatoreb said:

How did he do that? I wouldn’t have guessed it possible.

Here is the story about the flight.  It’s quite a feat considering how small the wings are.

http://home.hiwaay.net/~sbuc/journal/high.html

Clarence

[Marauder]

O2 debt affects different people differently. Fitness level and even age have much less to do with it than you would think. Both my brother and I seem to function pretty good up high, but I've had passengers that couldn't talk right past 18K. 
Cruising at FL200 with another pilot, we tested the effect of taking the mask off while the other pilot flew the plane. The difference between the two of us was night and day.

Whut yuo meen? I feal fin heer at 2,000 foot dunsity alltutude.

[Jerry Pressley]

day after i got my license i flew an ercoupe to 13,000 ft to get on top.    took 2.5 hours to get up there.  to make it mooney specific i was going to Lebanon Tn to look at a mooney for sale.

[jaylw314]

1 hour ago, M20Doc said:

Here is the story about the flight.  It’s quite a feat considering how small the wings are.

http://home.hiwaay.net/~sbuc/journal/high.html

Clarence

Holy smokes!  9 inHg of MP!

Impressive what you can get with a light and low-drag plane!

[jlunseth]

You guys are more patient than me.  Being there is one thing, getting there another.  I am not good at tolerating sub-500 fpm climb rates. 

The controls don't get mushy unless the airspeed does.  The K and J are basically the same airplane except for the engines, and we K drivers don't have a problem with mushy controls up into the flight levels unless, of course, you are trying hard to climb.  Vx increases with altitude, which tells you that the airfoil needs more speed to generate the same lift, but it is a meager 1.5 kts per 5,000 feet, so the change is 3 kts at 10k, 4.5 at 15 k, etc.  Its not much.  Airspeed makes a difference, and if you are losing horsepower and trying to climb that might create mushy controls, but at 160+ kts at cruise the controls don't feel any different at 21k than at 10k.

[aviatoreb]

1 hour ago, acpartswhse said:

day after i got my license i flew an ercoupe to 13,000 ft to get on top.    took 2.5 hours to get up there.  to make it mooney specific i was going to Lebanon Tn to look at a mooney for sale.

Hah!

i have 45 min of eurcouope time in my logbook.  I think all of it was climbing to pattern altitude.

[gsxrpilot]

1 hour ago, jlunseth said:

You guys are more patient than me.  Being there is one thing, getting there another.  I am not good at tolerating sub-500 fpm climb rates. 

The controls don't get mushy unless the airspeed does.  The K and J are basically the same airplane except for the engines, and we K drivers don't have a problem with mushy controls up into the flight levels unless, of course, you are trying hard to climb.  Vx increases with altitude, which tells you that the airfoil needs more speed to generate the same lift, but it is a meager 1.5 kts per 5,000 feet, so the change is 3 kts at 10k, 4.5 at 15 k, etc.  Its not much.  Airspeed makes a difference, and if you are losing horsepower and trying to climb that might create mushy controls, but at 160+ kts at cruise the controls don't feel any different at 21k than at 10k.

I can't tell any difference in the feel of the controls at FL260 which is as high as I've been in the Mooney. And I've been there many times.

[Steve W]

Looks like the flight I did in my M20J to test up to 17,500 I was doing about 200FPM at 0C, 30.15. Garmin was saying a DA of 19240ft and 128 KTAS once I was level. I did it as a step climb so I didn't really keep track of how long to get up there. 

I was solo with about 3/4 tanks of fuel.

[jlunseth]

2 hours ago, gsxrpilot said:

I can't tell any difference in the feel of the controls at FL260 which is as high as I've been in the Mooney. And I've been there many times.

I have only been to 24 which is the service ceiling in my aircraft (your 252’s is higher). But the Acclaim S guys fly at 24 and 250 regularly.  At 242 kts., I have not heard any complaints about mushy controls from them either.  Now, if you are climbing in an NA and can’t hit 300 fpm anymore, and your KIAS is down below a hundred, probably you will have weak control, but it is the climb that is doing it.

[FloridaMan]

I've had my M20F up to 17,000 a couple of times. It takes a while to get up there. The controls feel lighter like you're in slow flight and if your mags have some time on them you might get an occasional misfire. The controls on the Rocket feels a lot better at FL240 than the M20F does at 17,000. I suspect wing loading and the corrugated surface on the elevator aids in yaw stability of the rocket. The M20F has always felt a bit slippery in flight, sortof like you're flying a surfboard. 

[1964-M20E]

On 8/28/2018 at 2:14 PM, M20Doc said:

Here is the story about the flight.  It’s quite a feat considering how small the wings are.

http://home.hiwaay.net/~sbuc/journal/high.html

Clarence

Cool that's awesome

 

 

[cliffy]

On 8/26/2018 at 3:42 PM, N201MKTurbo said:

 

Just got back today from here! Didn't see the Mooney there :-)

During the 911 VFR shut down I did LAS to ABQ IFR at up to 15,000 in my D. Had "maybe" 200fpm climb up there. Finally had to have a block altitude for downdrafts that I couldn't handle. These days I do 11,000 max as at my "advanced" age I don't do up higher as well as I used to.

EVERYONE has there own resting, sea level physiological altitude where your body, even at sea level, reacts as if it is at a higher altitude to start with. Everyone is different. ALL the TUC time charts were done with young physically fit, military pilots. Are you still young and in good shape?  The TUC tables are nothing but wishful thinking AND they had an event marker to start the timing. Totally useless in an unpressurized airplane.  Here's a question to answer to yourself- If you O2 failed, WHEN did it fail? You may never know.

How long will it take you to get down? I'll guarantee you won't make it in the time you estimate right now. Watched too many times as jet drivers tried it the first time a blew it big time. 

Hypoxia is a sneaky little bastard.

Do yourself a BIG favor-Go take the FAA mixed gas experience at Oshkosh. Better yet, get a full chamber ride. You will never forget it or what you learned!

 

[Shiny moose]

I have to agree with the last post, get an altitude chamber experience.  I got my opportunity in 2000 and it was an eye opener for me.  Of course everyone is different at altitude but also it could be just a different day for you that causes the effects to become a real problem for you or your passengers. During my chamber ride, my friend was not smart enough to put his mask back on after being told 3 times, and eventually the chamber maid(sorry ) had to put his mask on for him. This was a good laugh for the rest of us as he was the last person to get the mask back on. He had no recollection of any problem or that he didn’t put on his own mask. So you people that think you don’t have any problems at altitude may not recognize that you are having degraded abilities to make simple decisions or even remember. I don’t think this is training you can do with a buddy in an aircraft pulling of the O2 and watching each other! What if your buddy became extreamly violent when deprived of O2, or decided its time to get out of the plane. Would you depressurize an aircraft at 25000 in flight just to see others be silly? Of course not. 

 

[Jerry 5TJ]

I “rode” the punp-down chamber about 3 decades ago, and this summer at at Oshkosh I participated in the FAA sea level training where the room’s oxygen is reduced to give a partial pressure equivalent to FL280. 

It is very impressive training packed into 15 minutes.  Sign up for the session if you possibly can.  

TUC is graphically demonstrated as you self-observe your rapidly plunging pulseOx levels and see what the othe 4 guys are doing.  

Rapid-onset O2 loss, such as cabin depressurization, is enough of a challenge but slow onset deprivation is even harder to detect.   

To address the OP question — I had my C and E Mooneys up to 15,000 a very few times.  I often flew at 10,000.  I had an O2 bottle strapped in the back seat and generally used it at 9,000 in the daytime. 

[mike_elliott]

11 minutes ago, Jerry 5TJ said:

I “rode” the punp-down chamber about 3 decades ago, and this summer at at Oshkosh I participated in the FAA sea level training where the room’s oxygen is reduced to give a partial pressure equivalent to FL280. 

It is very impressive training packed into 15 minutes.  Sign up for the session if you possibly can

CAMI will have the PROTE chamber at the Mooney Summit VII next year for our hypoxia training. It has taken me 6 years to get this done, now we are on their schedule!

 

[Jerry 5TJ]

1 hour ago, mike_elliott said:

CAMI will have the PROTE chamber at the Mooney Summit VII next year for our hypoxia training. It has taken me 6 years to get this done, now we are on their schedule!

Great!  

They run 5 pilots through at a time. 

Bring your current medical or a pix of same in your phone.  

[kortopates]

2 hours ago, mike_elliott said:

CAMI will have the PROTE chamber at the Mooney Summit VII next year for our hypoxia training. It has taken me 6 years to get this done, now we are on their schedule!

 

We also got our PROTE visit to San Diego scheduled for the week before Thanksgiving 2019 at Gillespie Field for those in the SOCAL area that would like to partake. 

[Hank]

1 hour ago, Jerry 5TJ said:

Great!  

They run 5 pilots through at a time. 

Bring your current medical or a pix of same in your phone.  

Looking forward to it! My medical is in the plane every time I fly . . . .

[Marauder]

1 hour ago, Jerry 5TJ said:

Great!  

They run 5 pilots through at a time. 

Bring your current medical or a pix of same in your phone.  

Do you think I should try to attend with my portable de-fib? I could charge (pun intended) by the number of zaps.

[cliffy]

Listen to how quickly hypoxia makes one "stupid". And, this is with a marker of pressurization failure. Without the "marker" you may never know you lost O2 and/or you may never be able to fix the issue or get down.

IN CAPS FOR A REASON- NEVER ASK PERMISSION IN A REAL EMERGENCY-DO WHAT NEEDS TO BE DONE AND THEN COMMUNICATE!

If he had just dumped it down immediately he might still be with us. 

[gsxrpilot]

5 hours ago, Shiny moose said:

What if your buddy became extreamly violent when deprived of O2, or decided its time to get out of the plane. 

Is that really a thing? 

It was a very simple exercise and no persons or Mooneys were harmed. 

Thanks, but I'm not worried.

[N201MKTurbo]

I was signed up to take the chamber ride in the old Air Force chamber at Williams-Gateway airport. I went on a tour of the chamber and talked extensively with the operator. He is older then the chamber. I eventually canceled my ride and got my fee refunded. That chamber is literally a death trap. I don't know how they are allowed to operate it. I am an engineer with an industrial automation company. I deal with safety regulations on a daily basis. Considering the silly safety concerns we have mitigate every day and then looking at the gross safety concerns I have with this chamber, it is a real head scratcher.

The chamber is impossible to open from the inside after it goes up even a few feet in altitude. There are no automated controls on the chamber. Just a switch to turn on the vacuum pumps and manual outflow and dump valves. There are no E-Stops of any kind anywhere. The vacuum pumps will take the chamber to 98000 feet. That will boil your blood and kill you without a space suit. They test space suits in this chamber. The way the chamber is operated, the door is closed and the pumps are turned on and the altitude rises. When it gets to the desired altitude the outflow valve is opened manually to maintain that altitude. To descend the pumps (2) can be turned off and the outflow valve is opened to get the desired descent rate. There is also a dump valve that can be used for rapid decent. This chamber has a second smaller chamber. If they want to do a rapid decompression they will pump the smaller chamber to say 80000 feet and then open a dump valve between the two chambers.

If the pumps were turned on and the lone operator was to pass out or have a heart attack, everyone in the chamber would die. 

I will not get into that chamber until there is an E-Stop installed inside the chamber that will stop the pumps.