rockydoc Posted September 17, 2014 Report Posted September 17, 2014 I'm normally aspirated M20B and routinely fly at 13,500 without any problem. Thin air, fast speed, minimal fuel burn. Life is good up there. Quote
carusoam Posted September 17, 2014 Report Posted September 17, 2014 And no bumps... And lots of altitude for plan B... -a- Quote
edwin Posted March 20, 2021 Report Posted March 20, 2021 For all you m20c pilots,, wondering what is your mp, and rpm at when you reach 15000 or 17000. On my m20c at 10500 i am square at 21,, full throtlle ,, any higher mp drops below rpm.. Quote
edwin Posted March 20, 2021 Report Posted March 20, 2021 Can anyone tell me what there mp and rpm are , at the 15 to 17000 ft altitude.. thks Quote
carusoam Posted March 20, 2021 Report Posted March 20, 2021 Where have you been Edwin? a post every few years...? Lets talk NA Mooney engine ops... Yes... MP drops off with altitude.... about 1” per 1k’... are you familiar with this rule? If you want to go faster... increase the rpm... this increase the amount of work the engine can do at that altitude... How far you take this idea is up to you... it helps to have a dynamically balanced prop for this... You are not turning the rpm down to match MP are you? Do you want to discuss leaning next? Best regards, -a- 1 Quote
spectre6573 Posted March 20, 2021 Report Posted March 20, 2021 Just Monday I popped up to 15500 for some weather. I saw 17-18 mp up there. I had my prop at 2600 rpm. I didn’t stay up there long because of the winds and up and down drafts. 1 Quote
RobertGary1 Posted March 20, 2021 Report Posted March 20, 2021 13 hours ago, spectre6573 said: Just Monday I popped up to 15500 for some weather. I saw 17-18 mp up there. I had my prop at 2600 rpm. I didn’t stay up there long because of the winds and up and down drafts. Get the glider rating man. You’ll ride those drafts up to the flight levels! Quote
A64Pilot Posted March 20, 2021 Report Posted March 20, 2021 18 hours ago, edwin said: Can anyone tell me what there mp and rpm are , at the 15 to 17000 ft altitude.. thks Standard lapse rate is 1” per 1,000 ft altitude, up to about 10,000 ft, after that the rate slows a bit. see table 4-2 https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/phak/media/06_phak_ch4.pdf Quote
gsxrpilot Posted March 21, 2021 Report Posted March 21, 2021 23 hours ago, edwin said: For all you m20c pilots,, wondering what is your mp, and rpm at when you reach 15000 or 17000. On my m20c at 10500 i am square at 21,, full throtlle ,, any higher mp drops below rpm.. First of all, no need to be square. My M20C would cruise as high as 16,000. MP was down around 18" or so, but prop still running at 2500 where I set it. 2 Quote
Guest Posted March 21, 2021 Report Posted March 21, 2021 A good friend of mine took his 180 HP normally aspirated RV-6 to 26000’ . Clarence Quote
edwin Posted March 21, 2021 Report Posted March 21, 2021 36 minutes ago, bluehighwayflyer said: I’ve taken my C up to 17,500’. Two men aboard and around 50 gallons. We have 64 gallon bladders and a PowerFlow exhaust. It was summertime en route from Pennsylvania to Noth Carolina. Nice.. do you recall were your rpm and mp ,were indicating.. Thks. Quote
edwin Posted March 21, 2021 Report Posted March 21, 2021 11 hours ago, gsxrpilot said: First of all, no need to be square. My M20C would cruise as high as 16,000. MP was down around 18" or so, but prop still running at 2500 where I set it. Thanks for the info...i will give my 20c the challenge later this week.. Quote
Christian Posted March 21, 2021 Report Posted March 21, 2021 I’ve had my M20C up to FL200 on a near standard day. Attached are a couple photos for reference. There’s a slight discrepancy between my G5 and the GTN650. I’ve included photos from each. IAS 109 MPH TAS 147 MPH (G5) 134 KTS (GTN650) I did this test just to see what the absolute ceiling of my bird was. I could have probably made it to FL220 but the climb was really starting to slow around 20,000 ft. Fun fact: At this altitude my Lycoming O-360 lost approximately 60% of its rated horsepower leaving me with approximately 75 horsepower. Few things worth mentioning… I was on an IFR flight plan. Class A airspace starts at FL180 so don’t even think about trying this unless you’re instrument rated. I was wearing an oxygen mask, not just a cannula. The FAA recommends the use of masks above FL180 at a flow rate of 2 lpm. 3 Quote
carusoam Posted March 22, 2021 Report Posted March 22, 2021 8 hours ago, edwin said: Thanks for the info...i will give my 20c the challenge later this week.. You didn’t mention some of the skills you probably have... Take a look at Christian’s post above... Regarding Class A airspace, IR flight plan, oxygen system, and mask type... don’t forget your O2 monitor... It will be hard to post your follow up, if you follow asleep on the way up... PP thoughts only, not a flight doctor or CFI... Best regards, -a- 1 Quote
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