M20k 305

[Stnelson903]

Hey all you M20k 305 rocket drivers. Tell me about your indicated airspeeds at various altitudes and the fuel flow to do it.

What some of your payloads with full fuel?

I don’t have the budget for the acclaim but could afford a 305.

Just the 305 guys please.

 

 

Sent from my iPhone using Tapatalk

[MIm20c]

As you wait for 305 guys to respond you might want to google “mooneyspace rocket” to get some background info.  Also the bravo is an alternative to the acclaim at half the price. 

Good luck on your search. 

[N201MKTurbo]

Last time I flew one I was at 16500, let me think, 32 inches 2300 18 GPH, 205 KTS TAS.

[aviatoreb]

29 minutes ago, N201MKTurbo said:

Last time I flew one I was at 16500, let me think, 32 inches 2300 18 GPH, 205 KTS TAS.

That doesn't sound right.  The speed is quite plausible but the engine setting sounds too lean, and too high an MP for the rpm.  At 32 2400 its 22gph and a bit faster, at 32 2300 is not permitted, and at 18gph book setting says 30'' and 2200 and that related to the speed you said.  Mine is 5-8knots slower than book though but I have tks and not the 252 belly mod.

[Yooper Rocketman]

I’ve had mine for 17 years.  I file 190 knots at 11k-12k, 200 knots around 18k and 210 knots at 23k-24k burning 19 GPH ROP at 30” manifold pressure and 2300 RPM. I have TKS so likely seeing 3-5 knot speed penalty from that.  It will climb at 1,000’ a minute right up to FL240.  Quite a bit better than that when ambient is cold, at lower altitudes when under gross.

I currently am 450 past TBO and it’s still running great.  Two exhaust valves since overhaul and both likely due to periods of inactivity.

Payload at full fuel depends on if you have extended range tanks.  The conversion comes with a gross weight increase that’s about 3 times the actual empty weight increase from the mod.  I’ve not seen the weight limitations any more challenging than most Mooney’s.

 

Tom

[N201MKTurbo]

3 minutes ago, aviatoreb said:

That doesn't sound right.  The speed is quite plausible but the engine setting sounds too lean, and too high an MP for the rpm.  At 32 2400 its 22gph and a bit faster, at 32 2300 is not permitted, and at 18gph book setting says 30'' and 2200 and that related to the speed you said.  Mine is 5-8knots slower than book though but I have tks and not the 252 belly mod.

That's why I said I think. All the settings were correct except the fuel flow, I don't remember.

[aviatoreb]

Just now, N201MKTurbo said:

That's why I said I think. All the settings were correct except the fuel flow, I don't remember.

:-). No worry.  That is a legit fuel flow and TAS.

[Marek7]

I plan about 200kts tas and 20 gph at 16000  it's typically less. Fuel flow but I'm typically taking off with min (planned) fuel so it's nice to be making fuel on the trip.   Send me a pm and we can talk details. 

[aviatoreb]

15 hours ago, Yooper Rocketman said:

I’ve had mine for 17 years.  I file 190 knots at 11k-12k, 200 knots around 18k and 210 knots at 23k-24k burning 19 GPH ROP at 30” manifold pressure and 2300 RPM. I have TKS so likely seeing 3-5 knot speed penalty from that.  It will climb at 1,000’ a minute right up to FL240.  Quite a bit better than that when ambient is cold, at lower altitudes when under gross.

I currently am 450 past TBO and it’s still running great.  Two exhaust valves since overhaul and both likely due to periods of inactivity.

Payload at full fuel depends on if you have extended range tanks.  The conversion comes with a gross weight increase that’s about 3 times the actual empty weight increase from the mod.  I’ve not seen the weight limitations any more challenging than most Mooney’s.

 

Tom

Im seeing similar speeds to you - and I even use a similar ff setting since I like 30''-2300 more than the suggested 30''-2200 that seems like more pressure in the engine.  Anyway we both have tks but I have been calling those same numbers maybe 5-8 slow and blamed the tks and you are calling it 3-5 slow.  Anyway we seem closely matched.

[Yooper Rocketman]

2 hours ago, aviatoreb said:

Im seeing similar speeds to you - and I even use a similar ff setting since I like 30''-2300 more than the suggested 30''-2200 that seems like more pressure in the engine.  Anyway we both have tks but I have been calling those same numbers maybe 5-8 slow and blamed the tks and you are calling it 3-5 slow.  Anyway we seem closely matched.

I claiming a speed loss based on before and after installation of the TKS.  I flew for 6 months prior to the install.  My original numbers, less TKS, were always less than the ones they sold the mod on ;>)

Tom

[aviatoreb]

26 minutes ago, Yooper Rocketman said:

I claiming a speed loss based on before and after installation of the TKS.  I flew for 6 months prior to the install.  My original numbers, less TKS, were always less than the ones they sold the mod on ;>)

Tom

Huh - I have heard some people claim book numbers for their rockets, and then some not - I have always had tks since I owned her so I don't have a before and after but mine seems at the end about similar to yours.

 

[Eraaen]

My fuel flows have never been as high as book.  I typically fly at 18/19k.  32/2400 ROP with 20.5GPH and see 210/215'ish TAS.  Some would say that might be pushing it, but my compression numbers have been continually been climbing over the last few years (probably because I'm flying often)  and I'm no longer getting the exhaust film on the belly when I was first trying to baby it, and leaning the heck out of it.  These settings keep the CHT's around 380 and TIT around 1530/1540

[aviatoreb]

6 hours ago, Eraaen said:

My fuel flows have never been as high as book.  I typically fly at 18/19k.  32/2400 ROP with 20.5GPH and see 210/215'ish TAS.  Some would say that might be pushing it, but my compression numbers have been continually been climbing over the last few years (probably because I'm flying often)  and I'm no longer getting the exhaust film on the belly when I was first trying to baby it, and leaning the heck out of it.  These settings keep the CHT's around 380 and TIT around 1530/1540

That is pretty close to book based on rpm/mp altitude and speed but on that setting 32/2400 and 20.5 you are running it 1.5gph lower than book recommendation.  Can you describe how you can to decide this fuel flow setting?  Is it the reasonable tit and cht or is that a certain number of degrees rop?

[Eraaen]

For me it has been based primarily on CHT with TIT as a secondary consideration. I pretty much stopped trying to find degrees ROP as it always seemed to be way to hot for my liking. As mentioned, fuel flows have never been as high as book. Even firewalled on take off I'm about 1.5 below book.  I know the totalizer is accurate when compared with refilling all 4 tanks.  It is spot on with totals.  Rather than throw money at it now (I'm pretty close to TBO) it just keeps running stronger.  I'll save my money until rebuild is required.  On a side note.  Sort of.  How do you guys determine when it's time to pull the trigger on a rebuild? When it makes metal? Hours? Compression? Oil Consumption?  I know they are all factors.  It just seems to me that way to many Turbo'd engines seem to be having top ends done every 600 hours around my home base.  I'm well beyond that with my settings.

[aviatoreb]

27 minutes ago, Eraaen said:

For me it has been based primarily on CHT with TIT as a secondary consideration. I pretty much stopped trying to find degrees ROP as it always seemed to be way to hot for my liking. As mentioned, fuel flows have never been as high as book. Even firewalled on take off I'm about 1.5 below book.  I know the totalizer is accurate when compared with refilling all 4 tanks.  It is spot on with totals.  Rather than throw money at it now (I'm pretty close to TBO) it just keeps running stronger.  I'll save my money until rebuild is required.  On a side note.  Sort of.  How do you guys determine when it's time to pull the trigger on a rebuild? When it makes metal? Hours? Compression? Oil Consumption?  I know they are all factors.  It just seems to me that way to many Turbo'd engines seem to be having top ends done every 600 hours around my home base.  I'm well beyond that with my settings.

The critical quantity is internal pressure but we have no direct measurement of that.  CHT relates closely to that.  The current thinking in many circles is just run by temp.  On the other hand I have been babying my engine compared to you - at 30'' 2300 most of the time. Maybe out of habit?

Maybe I will play around with the higher settings you do and see what its like.  I do know that my CHTs tend to be extremely (too?) low as by book.  To rich is not good either.  Not only do you give up horsepower, dump fuel needlessly, but also this fouls up your engine with lead deposits so I hear.

I once had a Cessna 402 poh in my hands and I notice that the fuel flows for given horsepowers are significantly lower by that book than they are in the rocket book. I tend to think the rocket book is very conservative with the fuel flow.

Much has been said about top overhauls.  The current thinking is that continental factory valves are made with very poor workmanship and they leak quickly in time in service and this is the reason we need top overhauls mid stream, and not because of how we operate our machines.  The cure is to custom lap -rework the valves before install even if it is a new cylinder straight from the factory.

When to overhaul - well that is a real zinger of a question - lots written about that - even on this forum. I won't enter that here.

But as for me I have a number written in stone by the FAA when I must overhaul.  I am at 1425 hrs, but I have titan cylinders that are subject to AD which means those cylinders must come off at 1990 hours as it turns out.  Then if I am replacing all the cylinders at 1990 - meh I will major overhaul my engine at that time - hoping I make it that far.

[FloridaMan]

You guys are making me jealous. I've got the money sitting here; just waiting for the right Rocket. It seems the three that are listed right now have been on the market for a long time. 

[MIm20c]

Real world TKS to TKS what is the TAS delta between the bravo and rocket? 5, 10, 15 kts? Fuel burn looks to be similar. 

[aviatoreb]

4 hours ago, MIm20c said:

Real world TKS to TKS what is the TAS delta between the bravo and rocket? 5, 10, 15 kts? Fuel burn looks to be similar. 

I only once flew in a bravo with tks but I found the speeds to be generally very similar.

[Yooper Rocketman]

On 3/6/2018 at 1:04 PM, Antares said:

You guys are making me jealous. I've got the money sitting here; just waiting for the right Rocket. It seems the three that are listed right now have been on the market for a long time. 

I’m at Spruce Creek until late next week.  Good time to look at one that will be on the market in the next 6 months!

Tom

[RocketAviator]

I have flown my Rocket since 2013 with just over 1000 hrs on it to date.  I regularly fly at 11-12k at 35MP, 2375 Prop @ 16 GPH  LOP @ 152 indicated, 192 TAS.  I can bump it up to the 21-24 GPH and run 207-210+/-.  I have flow it a few times ROP close to the factory placard settings and achieved 224 TAS @ FL21.  I limit my settings to not exceed TIT 1650 & CHT to 375.

Take off fuel burn can be absurd @ 33.2 GPH is I push it.  It will climb fuel full 2 people in hot weather @ 1200+ft as high as I have ever wanted to spend the fuel getting there.

Payload never an issue.

I do not have long range tanks 75 gal only usable!

If I slow it down I can burn 9.5 GPH and go much further than my body will permit!  Otherwise my max is about 3.5 hr with my personal reserves!

I almost put my Rocket up for sale this last year as I only flew it just under a 100 hrs....  But after a lot of thought I decided its paid for, it was the plane of my dreams for me as I had the avionics & panel completely redone when I purchased it with G500, GTN 750, 650, engine analyzer.  Then spent a number of hours and trips to GAMI to get the injectors just right.

Good luck, I hope you find one as good and have as good an experience as I have had with mine.

[M016576]

13 minutes ago, RocketAviator said:

I have flown my Rocket since 2013 with just over 1000 hrs on it to date.  I regularly fly at 11-12k at 35MP, 2375 Prop @ 16 GPH  LOP @ 152 indicated, 192 TAS.  I can bump it up to the 21-24 GPH and run 207-210+/-.  I have flow it a few times ROP close to the factory placard settings and achieved 224 TAS @ FL21.  I limit my settings to not exceed TIT 1650 & CHT to 375.

Take off fuel burn can be absurd @ 33.2 GPH is I push it.  It will climb fuel full 2 people in hot weather @ 1200+ft as high as I have ever wanted to spend the fuel getting there.

Payload never an issue.

I do not have long range tanks 75 gal only usable!

If I slow it down I can burn 9.5 GPH and go much further than my body will permit!  Otherwise my max is about 3.5 hr with my personal reserves!

I almost put my Rocket up for sale this last year as I only flew it just under a 100 hrs....  But after a lot of thought I decided its paid for, it was the plane of my dreams for me as I had the avionics & panel completely redone when I purchased it with G500, GTN 750, 650, engine analyzer.  Then spent a number of hours and trips to GAMI to get the injectors just right.

Good luck, I hope you find one as good and have as good an experience as I have had with mine.

What’s the useful load on your rocket?

[RocketAviator]

Spreadsheet says 858.3# Useful load ......  Sufficient for myself and my wife and the occasional grand-kid or two!   

 

[Richard Knapp]

RocketAviator, can you tell us what TAS you get at 9.5 GPH in your Rocket.  Also, what speed you are at with 1200fpm climb at 33.2 GPH?  Do you have TKS? It would be helpful to me to know. Thanks!

[RocketAviator]

Richard, I am sorry I dont recall what TAS I get at 9.5 or at that TAS @ 1200 ft climb.  As you know there are factors that affect true numbers like weight etc...

I recall flying with Bucko who has an E and we have flown several multi-hour flights at around the 9.5 or even lower fuel flow rates but I am sorry do not recall the TAS as we were mainly in formation flight.  I recall it being impressive at least to me though.  I use my Rocket for a go-to place to place with an average trip of 550 kt miles which we often make multiple times a month on a normal basis.  For that mission, I am now flying at 34 MP, 2375 Prop and 16.0 gph at 190 TAS down low @ 11-12 as I now only have basic med.

Do not have TKS only hot prop and only 75 gal fuel.

What are you attempting to learn of come up with?

[Jeremy95]

I see about the same. FF numbers slightly lower than book numbers for given power settings/tit limits, somewhere between .5 to 1 gph less. I also get about 5-8 knots less than the book numbers. Typically fly the 72% power settings. For climb I usually power back to the 88% power setting and around 110 kias not climbing above about 12k feet I see about 1000-1200 fpm in the climb. 

CHTs 380 or less at cruise depending on where cowl flaps are at and how far ROP. My ff full rich at TO power is set a gallon or two higher than the book numbers but full rich in the climb does keep things very cool.