305 Rocket VS 262

[austen]

Looking for input on owners with real life experience. 
 

Looking at comparing speeds for 1,000 nm trip for M20K 262-MB engine vs M20K 305 Rocket. 
 

I’m familiar with the engine differences, need for Monroy tanks, etc. 
 

Looking for TAS for 262/305 at 6,000 feet, 10,000 feet, 14,000 feet. 
 

My missions are 1,000 nm+ and just wondering which one would be best. I DO NOT plan on going 20,000 ft+ to hit the true super speeds of either airplane. <18,000ft only 

[Fly Boomer]

41 minutes ago, austen said:

Looking at comparing speeds for 1,000 nm trip for M20K 262-MB engine vs M20K 305 Rocket. 

The only big difference between the two is 200 hp vs 300 hp.  That said, while it sounds like a lot, a 50% increase in horsepower only makes maybe a 10% difference in speed.  BUT on a 1000 nm trip that will make a significant difference.  Also, time to climb to altitude will be substantially less with the Rocket, so more time spent at cruise speed.

Watch this space for other opinions.

[N201MKTurbo]

You forgot 11 GPH vs 16-18 GPH.

[Fly Boomer]

8 hours ago, N201MKTurbo said:

You forgot 11 GPH vs 16-18 GPH.

Details, details.  FOR THE OP:  going faster burns more gas, but the whole reason for a Mooney is to go fast.  

[Z W]

In a 262 - At 6,000, I plan 150 KTAS. At 10,000, 160 KTAS. At 14,000, 165 KTAS.

All on 12.5 GPH. Some run LOP and do more like 10.5 or 11 GPH but my engine doesn't run well there.

I've done a few 1,000 NM flights non-stop but don't like it and you shouldn't count on doing it reliably. The plane will do it with extended tanks but that's almost 6 hours in the air at 170 KTAS, no wind. I've only done it with a tailwind. A headwind can easily require a fuel stop. More importantly, when you go 1,000 NM, you will almost always encounter weather along the way, requiring detours or even sometimes that you stop and wait for it to clear.

I believe a rocket may actually have worse endurance (range) due to it's higher fuel burn not being offset by its faster cruise speed.

1,000+ NM flights non-stop on a schedule is not a piston airplane mission. You need a jet.

[201er]

11 hours ago, austen said:

Looking for TAS for 262/305 at 6,000 feet, 10,000 feet, 14,000 feet. 

My missions are 1,000 nm+ and just wondering which one would be best. I DO NOT plan on going 20,000 ft+ to hit the true super speeds of either airplane. <18,000ft only 

More of a question of Missile vs Ovation then

[exM20K]

2 hours ago, 201er said:

More of a question of Missile vs Ovation then

Airplanes climb on excess power, so the Rocket will have an advantage in climb.  However @austen wipes most of that advantage away by staying low.

Let's assume the fuel specifics of the TSIO360MB and the TSIO520NB are the same (I suspect the tuned induction TSIO360MB is more efficient, though), then the miles per gallon should be the same at the same fuel flows.  Except…. The Rocket is less aerodynamically efficient: it has a very far forward CG as compared to the 252, so the tail is doing much more work thereby creating more induced drag.

Max range will require a low, LOP power setting.  Will a rocket run LOP? I don’t know.

Anyway, 1000NM trips are outside the practical range of any non-pressurized piston plane. I regularly do 750NM in an Acclaim, and I typically land with 8-10 gallons of “extra” fuel, so maybe another 100 miles till legal reserves. That is at 225 HP, so one could maybe another 150 NM by reducing power a bunch. But 6-7 hours at oxygen altitude is not something many would want to do. Exhaustion, the likelihood of crossing multiple weather systems, and sucking O2 all point to a >250 KTAS pressurized plane.

The attached range/endurance chart for the Acclaim is probably 5% too optimistic.

Get yourself an Aerostar, TBM, or MU2.

-dan

[Schllc]

55 minutes ago, exM20K said:

Get yourself an Aerostar, TBM, or MU2.

they say the aerostar has a 1000 mile range but that would only be on the 700 with the extended range tank, and that would only be under ideal circumstances.

The 601p or 602p does not have 1000 mile range.

[N201MKTurbo]

It is hard to justify flying a Mooney that far for a work trip. I work for a company in NC. The airlines will get me there in 6 hours or so for a lot less money. I guess it depends where you are going. I had a work trip once where I needed to go from Phoenix to Iowa City. The airlines took 11 hours door to door. Then I took the Mooney and it was only 9 hours door to door.

[Fritz1]

As stated before 1000 NM is typically out of the range of a piston single, I have done 900 NM trips in the Bravo going east at 21,000 ft TAS 188-190 Kt with TKS, fuel flow 18-18.5 gph with strong tail wind, oxygen, weather systems, this is about as far as she will go with 100 gal tanks, landing with 17-18 gal, pilot typically needs some rest thereafter, I would look at the CG envelope and how both engines and airframes are supported, parts availability, presumed dispatch reliability, Jimmy Garrison at GmaxAmerican knows the ins and outs of both models since he has sold a lot of them, might be worth while to give him a call, enjoy the journey!

[Max Clark]

15 hours ago, austen said:

Looking for TAS for 262/305 at 6,000 feet, 10,000 feet, 14,000 feet. 

My missions are 1,000 nm+ and just wondering which one would be best. I DO NOT plan on going 20,000 ft+ to hit the true super speeds of either airplane. <18,000ft only 

My Ovation's sweet spot is ~10k MSL, when I start climbing above 12k I notice the performance drop and try to avoid doing so. I end up cruising 165 TAS LOP @ ~11 GPH.

My daydreams are Turbo/Turboprop specifically to fly higher, faster, and farther. I couldn't imagine spending the Turbo money on an Acclaim or Rocket and then flying it low. Talking with Turbo plane owners the low FLs are where it's at.

My "long" mission charts at the 928nm mark. But with MOAs and weather is always longer (1,153.9 and 7.9 hours last time). Hence my daydreams of flying higher and faster to get over those MOAs and weather. While a non-stop pencils out at 928nm it definitely doesn't over 1,100nm.

The Ovation is a comfortable plane to be in, but I notice myself really wanting a break after four hours. I find flying 3-3.5 hour legs is much more reasonable and comfortable.

Instead of the one-stop I'm likely going to switch to a two-stop in the future.

[N201MKTurbo]

After 22 years of owing a turbo, here is what it is good for, IMHO.

1. Getting over weather.
2. Flying over the mountains. 
3. Going eastbound.
4. Going faster on long trips.

It takes so long to climb and descend, it is hardly worth it for a trip less than 2 hours.

With no FIKI ice will often keep you from going up high.

Often times the turbo speed advantage is canceled by the wind speeds.

Remember 2/3 of all winds are a head wind.

All that being said, the turbo does give you more options.

FIKI would give more capability than a turbo.

[201er]

6 hours ago, Z W said:

In a 262 - At 6,000, I plan 150 KTAS.

I've done a few 1,000 NM flights non-stop but don't like it and you shouldn't count on doing it reliably.

Same speed in a 201 at 6000. If higher altitudes aren’t required, a 201 ER can do 1000nm with comfortable IFR reserves (landing with close to 3 hours fuel).

150KTAS nonstop is comparable to 170 with a stop (on 1000nm). Basically triple priced Mooney is the price of pissing on the ground instead of in the air 

[Ragsf15e]

As others have said, I wouldn’t really want to do this often, however…

I have a 252 updated to the SB engine (encore upgrade) with extended tanks.  You can get 104-110 gallons in depending on how persistent you are.  I cruise at ~175ktas around 15,000’ at 65% power burning 10.4gph.  Mine runs lean of peak well, others might have some issues and rop or book (which is about peak) costs more fuel for the same speed.  So I count 15gallons for the first hour (climb is 26gph!), 11 gph thereafter (10.4 if you want to be exact).  That gets you 7.5hours with 15gallon reserve.  If you multiply that by 175ktas, you will see a range of 1200nm no wind.  That doesn’t sound fun, it doesn’t account for westbound winds, requires you to be in the mid/upper teens sucking oxygen for 7 hours, and crosses several fronts.  It’s probably useful on rare occasions, not a normal flight.

[N201MKTurbo]

I have reached a point in life where 4 hour legs are all I want to do. More than that stops being fun.

[Schllc]

1 minute ago, N201MKTurbo said:

I have reached a point in life where 4 hour legs are all I want to do. More than that stops being fun.

Absolutely…

I did a 6+ hour flight in my ovation, from south Florida to Austin about 8 years ago. First and last time I ever will do more than 4.5. There was little enjoyable in that journey. 
I plan for under four hour legs, but occasionally push when it’s just over 4.

[Z W]

3 hours ago, 201er said:

Same speed in a 201 at 6000. If higher altitudes aren’t required, a 201 ER can do 1000nm with comfortable IFR reserves (landing with close to 3 hours fuel).

150KTAS nonstop is comparable to 170 with a stop (on 1000nm). Basically triple priced Mooney is the price of pissing on the ground instead of in the air 

I try not to fly as low as 6,000, but the OP asked for speed there. My preferred altitudes are 15-17k. If I'm lower, it's for weather, headwinds, or short distances.

After getting used to being up there, I find it hard to consider going back to a naturally aspirated engine, even after paying for a turbo overhaul this year. Smooth air, good radio reception, plenty of glide range, direct routing, and very little traffic make it all very enjoyable. It still surprises me sometimes how much weather you can top at 15k, visual and in the clear.

The speed is a bonus when you happen to get it, but is not the point.

I plan 3-3.5 hour legs and pretty much never use the extended range tanks. I'll do two legs of that length in a day which lets me do about 1,000 NM comfortably, but not in one leg. 

[austen]

Okay, let me riddle the group this: 

 

All fine and dandy when there’s a tail wind to go high; 252/262/Rocket. 
 

The real question is staying low to stay out of the winds that have a higher lapse rate than the TAS of the plane. I found myself flying at 6-7-8-9k feet westbound in my old Mirage. 
 

I NEED TO CROSS THE ROCKIES 50% of the time and have the capability of at least 16k. 

I have a Citation for when the weather is bad or hauling Pax. Sometimes, when it’s just me, I’m okay with going back to the basics! I’ll do 7 hour legs with movies, snacks… and a few travel Johnnies hehe

[Will.iam]

The rocket you can go fast when you want but drink down the gas but it is an option. The 252 you will be the stingiest on gas, but you will not go faster than the rocket unless you get above 14-15k or so. The rocket if you throttle it back to the 252 speeds at 10k will be close to but not equal the 252 in fuel burn. I think if it were me i would rather have the 252 for altitude options for weather compared to the extra speed especially since it would only result in extra fuel stops thus defeating the over all goal of the race. Think tortoise in the hare. 

[N201MKTurbo]

17 minutes ago, austen said:

Okay, let me riddle the group this: 

 

All fine and dandy when there’s a tail wind to go high; 252/262/Rocket. 
 

The real question is staying low to stay out of the winds that have a higher lapse rate than the TAS of the plane. I found myself flying at 6-7-8-9k feet westbound in my old Mirage. 
 

I NEED TO CROSS THE ROCKIES 50% of the time and have the capability of at least 16k. 

I have a Citation for when the weather is bad or hauling Pax. Sometimes, when it’s just me, I’m okay with going back to the basics! I’ll do 7 hour legs with movies, snacks… and a few travel Johnnies hehe

Buy the Rocket. If you run the engine at its max, that thing will haul.

[N201MKTurbo]

1 hour ago, Will.iam said:

The rocket you can go fast when you want but drink down the gas but it is an option. The 252 you will be the stingiest on gas, but you will not go faster than the rocket unless you get above 14-15k or so. The rocket if you throttle it back to the 252 speeds at 10k will be close to but not equal the 252 in fuel burn. I think if it were me i would rather have the 252 for altitude options for weather compared to the extra speed especially since it would only result in extra fuel stops thus defeating the over all goal of the race. Think tortoise in the hare. 

The Rocket is turbo charged. Why would the 252 outrun it above 15K? The last time I flew a Rocket at 16000 I was doing like 210 KTS.

[Fly Boomer]

1 hour ago, austen said:

I NEED TO CROSS THE ROCKIES

You will hear a chorus of "I do it all the time with my NA airplane" but, for me, Rockies=Turbo.  The ground is hard.

[Will.iam]

51 minutes ago, N201MKTurbo said:

The Rocket is turbo charged. Why would the 252 outrun it above 15K? The last time I flew a Rocket at 16000 I was doing like 210 KTS.

Whoops i mixed up rocket with missile. I will go back under my rock now. 

[1980Mooney]

15 hours ago, austen said:

I NEED TO CROSS THE ROCKIES 50% of the time and have the capability of at least 16k. 

I have a Citation for when the weather is bad or hauling Pax. Sometimes, when it’s just me, I’m okay with going back to the basics! I’ll do 7 hour legs with movies, snacks… and a few travel Johnnies hehe

If you need to cross the Rockies 50% of your missions, then don't you really need FIKI?  I get it, that you will take your other plane if weather is projected to be bad.  But your "mission" is two way.  You run the risk of getting across the Rockies to your 1,000+ NM destination on one part of the week, only to be grounded (or greatly diverted) on the return due to freezing precipitation over the Rockies on the date of the return.  It is like a pilot that is not Instrument Rated the embarks on a cross country trip on a nice day only to get stuck by a front on the return.

The 262 was an MB engine conversion of the 14 volt 231 by defunct Mod Works.  The Rocket might be 14 v or 28 v depending on the donor plane.  You won't find a FIKI 262 because they are 14 v.

[wombat]

Real world Rocket owner here.     

A consistent 1,000 NM range is unrealistic for any Mooney.   At least in my Rocket (which is a little on the slower end) I wouldn't count on 1,000 NM in any direction but East, and even then I ned a pretty good tailwind and willingness to climb high.

Re: FIKI...  FIKI is nice, but a non-FIKI TKS is functionally similar.   The FIKI changes are redundancy and a heated stall vane.  The TKS panels are technically different, but functionally the same.   As long as everything works and nothing breaks the only difference is the stall warning horn.   So be careful when/where you fly.   Look at the SKEW-T  LOG-P diagrams to find an altitude that is likely to not have ice.   Don't plan to land at a short runway unless you know the stall warning will free after any ice encounters. Always have an out or two.  But an AIRMET is not "Known Icing Conditions", neither is a PIREP from any time before now.  But with that being said: don't be stupid.  Or as they say:  "Fly good.  Don't suck."

 

And @1980Mooney referenced this knowledge but to make it very clear: CAV Ice doesn't make a FIKI install for a 14V system for Mooneys so if you have a 14V plane it's not possible to get a FIKI system on it without paying for the certification which is probably in the $10,000,000 range to accomplish.

 

https://www.noaa.gov/jetstream/upperair/skew-t-log-p-diagrams