Time to Climb

[Hank]

35 minutes ago, cnoe said:

+1 for Jiffy.

Sorry Hank but 40 years ago, before the advent of 7-11, my parents owned a small convenience store called Jiffy Mart. I got all the free Icees I could drink, so I'm biased.

I remember Jiffy Mart! Orange sign with the tops of all the white letters curled down? We had them in Auburn when I was in college, less than 40 years ago. But I was getting Slurpees at 7-11 in elementary school. Guess it depends on what part(s) of the country you are / were in.

need to bust out the calculator and see how much time a Jiffy is, since it's defined by light moving a tiny fixed distance, and compare it to a shake, which is simply 10^-8 seconds. I'll go for the smallest one.

on the other hand, furlongs per fortnight yields pretty big numbers. 140 mph indicated becomes 376,320 FPF. Imagine that on your AI!!  

[Joe Zuffoletto]

Roberto Tohme did this in his Acclaim a few years ago, comparing time to climb from his 3,920' field elevation (KELP) to FL250 before and after adding the 310hp STC. His spreadsheet is attached. This was the data that made me decide to go for the STC on my Acclaim as well.

I was going to play hooky today and to this myself, but we have lots of wind and turbulence right now. Some other day....

Acclaim climb performance.xls

[pfactor]

I posted time to climb data before and after installing the PowerFlow exhaust in my M20J. The post has charts and everything!

The short version:
Before PowerFlow: 33 minutes to get from sea level to 14,000 indicated (16,000 density altitude).
After PowerFlow: 42 minutes to get from sea level to 17,000 indicated (18,000 density altitude).

Phil

[carusoam]

In that case...

Use the standard for Mooney climb rates...

Apparently 1RT = 1000fpm

RT for Roberto Thome, the king of the Mooney climb!

I was expecting a number closer to 2kfpm for the TN'd IO550 climbing out at 115Kias turning 2700 rpm.  Or did I miss something?

Joe, Wishing I was in Denver. I'd love to ride along and help collect data for your trip.  As usual, please double check your O2 systems. 25k' can be unfriendly to human existence.

I look forward to that performance Pirep.

Best regards,

-a-

 

[Joe Zuffoletto]

30 minutes ago, carusoam said:

I was expecting a number closer to 2kfpm for the TN'd IO550 climbing out at 115Kias turning 2700 rpm.  Or did I miss something?

Joe, Wishing I was in Denver. I'd love to ride along and help collect data for your trip.  As usual, please double check your O2 systems. 25k' can be unfriendly to human existence.

I look forward to that performance Pirep.

Best regards,

-a-

 

One thing missing from Roberto's data is the weight of his aircraft. His climb rates lead me to believe he had full tanks. I've seen 2,000fpm climbing out of Leadville with half tanks. The difference between 50 and 100 gallons is significant!

Anthony, get your butt out here! Plane tickets are cheap! BTW, I don't plan to climb to FL250. Probably just FL180 or maybe FL200.

[cnoe]

Okay, I just got back from completing my "TIME TO CLIMB" and here's the results. A couple of notes and thoughts will follow.

1978 M20J

Field elevation: 25 MSL

Temp: 23 C

Alt: 29.86”

DA: 1,020’ (initial)

Weight (est.): 2,070# (incl. 24 g. fuel)

IAS: 102-97 MPH

Alt.         Time      Leg         FPM

25           0:00

1000      1:10       1:10*     836*

2000      1:58       0:48       1250

3000      2:48       0:50       1200

4000      3:34       0:46       1304

5000      4:35       1:01       984

6000      5:34       0:59       1017

7000      6:41       1:07       896

8000      7:43       1:02       968

9000      9:02       1:19       760

10000    10:20     1:18       769

11000    11:52     1:32       652

12000    13:34     1:42       588

13000    15:29     1:55       522

14000    17:27     1:58       509

15000    19:39     2:12       455

16000    22:22     2:43       368

17000    25:23     3:01       332

18000    28:40     3:17       305

*Includes take-off roll

NOTES:

DA @ 18,000’ = 19,768 (calculated).

Obviously I was fairly light @ 670# below gross, but I often fly light.

My climb rate varied a bit at the lower levels with varying airspeed due to light turbulence, but I generally held IAS @ 100 MPH.

Settings were WOT, ~2,700 RPM, & ~200 ROP throughout climb.

At Vy I had to open cowl flaps to trail position @ 9,000' due to high oil temp (225 F.) and I left them there to 18,000'.

At 17,900' my MP was ~15 (14.6 on JPI-830) and %HP (on JPI) was 52% (photo attached).

I was very pleased with the performance to 15,000' but then it starts to fall off quickly. Still it's nice to know that if I HAVE to get to 18K+ I CAN.

FYI, according to my JPI the fuel burned to reach 18K was ~6.8 gallons.

Fun stuff indeed. Who's next?

Cnoe

 

[ArtVandelay]

You said you were 200 ROP, but your JPI shows 1393 for EGT on cyl 1, are you saying your normal EGTs are 1600?

[cnoe]

1 hour ago, teejayevans said:

You said you were 200 ROP, but your JPI shows 1393 for EGT on cyl 1, are you saying your normal EGTs are 1600?

Nothing gets by you guys!  Good eye.

Here's the answer: #4 is typically my first to peak, and it's also my hottest EGT at a (usual) peak of ~1,495-1,500. Cylinder 4's EGT in the pic reads 1,396 if you zoom in. I see on my scribbles from the flight that I leaned to 100 ROP @ 17,500' so my statement (200 ROP to altitude) was slightly erroneous. To be accurate I'll admit that maintaining the EGTs at 200 ROP was the lowest of my priorities and several times they were richer than that; I don't think I leaned at all until I was pretty high (which might explain why my 6K-7K leg was slow).

The other thing that I should mention is that I only went to 17,900' pressure altitude (note the altimeter set at 29.92") as my transponder/ADS-B was broadcasting pressure altitudes about 50' higher than my altimeter reading and I didn't want to get a call for busting Class Alpha. To compensate for the 100' shortage I added 20 seconds to the final leg's time to reflect a full 1,000' climb from 17,000' to 18,000'. The moment that picture was taken I was 10 seconds from leveling off at 17,900'.

It really didn't look much different at 17,900 AGL than at 12,000, but it was pretty cool knowing I could glide close to 30 miles with no engine.

Also, I ran 2 lpm in my nasal canula in the upper altitudes and my O2 saturation was 97-98% throughout.

[bonal]

Hoping to make my climb soon. Obviously model type will be a factor I'm curious what my down range will be as I reach my target altitude 

[cnoe]

Pardon my ignorance but what do you mean by "down range"? Gliding distance?

I did not measure that; 30 miles was just an estimate. I ran 16"-18" and 2,200 rpm most of the way down. With some tailwind I was showing over 235 kts. at one point in the descent while still well in the green arc IAS.

I should also mention that my older S-Tec altitude hold was having a hard time maintaining a fixed level in the thin air. I'd never considered that before.

Sent from my iPad using Tapatalk

[bonal]

Down range meaning how many miles from departure by the time you reach target altitude 

[cnoe]

Oh. Seems obvious now but since I was flying into a STRONG headwind no useful distance data came from my test flight. My Cloud Ahoy app showed a 49 kt. headwind at 17K-18K MSL so I wasn't getting anywhere quickly. I usually climb enroute at 120-125 mph instead of 100. And I try to avoid 50 kt. headwinds too.

Someday I'd like to do it all over again at gross to see the difference.

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[ArtVandelay]

Pardon my ignorance but what do you mean by "down range"? Gliding distance?

I did not measure that; 30 miles was just an estimate. I ran 16"-18" and 2,200 rpm most of the way down. With some tailwind I was showing over 235 kts. at one point in the descent while still well in the green arc IAS.

I should also mention that my older S-Tec altitude hold was having a hard time maintaining a fixed level in the thin air. I'd never considered that before.

Sent from my iPad using Tapatalk

My 78J cowl flaps don't have positions, it's open or closed, any other positions are not stable. What do you mean by trailing? Do you have electric cowl flaps ?

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[carusoam]

CloudAhoy seems to be the App to use for recording flight data details.

Combine with a WAAS source like SkyRadar, it records accurate T/O and landing distances.

CNOE, how did CloudAhoy collect the headwind component?

In the past, I asked questions by email direct to Chuck Shavit at CA.

Best regards,

-a-

[Guest]

5 hours ago, teejayevans said:

My 78J cowl flaps don't have positions, it's open or closed, any other positions are not stable. What do you mean by trailing? Do you have electric cowl flaps ?

 

 

 

Sent from my iPhone using Tapatalk

The J models with cable controlled cowl flaps have only open or closed position. However in the manual it says that you can adjust the rod length so that in the closed position they are slightly open.

Clarence

[kmyfm20s]

My 82 J had 3 positions. All the way open, slightly open(trailing) and closed.

[The-sky-captain]

32 minutes ago, kmyfm20s said:

My 82 J had 3 positions. All the way open, slightly open(trailing) and closed.

Mine too...

[cnoe]

1 hour ago, kmyfm20s said:

My 82 J had 3 positions. All the way open, slightly open(trailing) and closed.

Same for me. There's not an "indicator" like with wing flaps but there's 3 distinct positions. This was first pointed out to me during Mooney type training.

You can "feel" the trailing position by positioning the control about mid-way between open and closed; it definitely has a setting that's almost like a "detent".

In my POH it says:

"Upon reaching cruise altitude, allow acceleration to cruise airspeed, then trim the aircraft for level flight, reduce manifold pressure and RPM to desired cruise power, and close the cowl flaps. The cowl flaps should be partially opened (control pulled aft approximately three inches) if necessary, to maintain the oil and cylinder head temperatures within the normal operating range."

I generally select "cowl flaps trailing" shortly after takeoff and throughout the climb to reduce drag unless oil and/or CHT temps dictate otherwise.

Also, make sure the "spring" is in place on the mechanism inside the lower cowl as I believe it helps keep the cowl flaps in the proper position. Mine was previously missing and it made the positioning less distinct.

[jetdriven]

I select cowl flaps trailing just before pushing the throttle for takeoff.  Even on the hottest days.

[kmyfm20s]

My "Time to Climb" results.

1999 M20S 310stc, Vy=105 kias

Myself and a passenger=380lbs, 50g of fuel=291lbs, bags=45lbs.

Field elevation -53, DA=814', Alt 29.95", Humidity 23%

Alt              Time           Leg           Temp

-60'-1000'   1:14                             22c

2000'          1:59         :45               21c

3000'          2:49         :50               20c

4000'          3:39         :50               18c

5000'          4:30         :51               16c

6000'          5:17         :47               15c

7000'          6:18          1:01            13c

8000'          7:12          :54              12c

9000'          8:16           1:04            10c

10,000'      9:22            1:06             9c

11,000'     10:29           1:07             7c

 

I started timing at the start of the ground roll. After 11,000' I got to busy to get accurate numbers. I will try to get higher on another trip.

[cnoe]

Wow! Excellent. 

What model plane???

[kmyfm20s]

I will edit. 1999 S with 310stc.

[cnoe]

I want one of THOSE! 

[kmyfm20s]

It was the only plane that could take me away from my J.

[DonMuncy]

On my 231, the trail position is a kind of free cowl flap position. One position "locks" them open, one "locks" the closed and in between allows them to open to the extent that the airflow dictates. At least that is how it seems to me.