TKS on Rocket

[230KT]

Hi all,

I'm in the market for a Rocket, and would like some opinions on whether buying one with a TKS system installed will reduce airspeed from the book values, and if so, how much?

[M20F-1968]

It will reduce payload much more than airspeed. You will loose about 2 kts.

[230KT]

The payload issue I understand. However, I've been told everything from a 10 KT loss (I assume due to increased drag and weight), to an INCREASE in airspeed because filling the fluid tank shifts the CG aft (so the horizontal stabilizer creates less negative lift.

I guess the bigger picture question is whether the Rocket will achieve the published true air speeds. I've been searching flightaware but haven't yet seen a Rocket flying 230KT at FL240.

[David Mazer]

I flight plan my non-TKS Rocket at 30" mg and 2200 RPM at 185 kts @ 12,000 ft and 17 gph, 200 kts @ 18,000 ft and 17.5 gph, and 210 kts @ 24,000 at about 18 gph. It will go faster but I rarely find it worth the gas. I have been told that TKS will slow the plane 2-5 kts depending on the installation. I believe it would be closer to 5 kts because I mistakenly painted a leading edge white stripe to cover some peeling paint and the trailing edge of that stripe wasn't smoothed out. When the plane was painted and the edge was removed, I gained almost 5 kts. I was shocked.

[FoxMike]

230KT,

I have TKS on my TLS. I occasionally fly a friend's TLS which has only a hot prop. No doubt in my mind the TKS causes a loss of performance on both the top and bottom end. I think it takes about 8kts off the top end. At 75% probably 6kts. I have owned two airplanes with boots and have noticed the boots cost a few kts. Flying at altitude means coming down through more clouds which usually means more icing encounters. I find the TKS to be useful even though it does not get used very often. I hate giving up the performance until I get into a bunch of ice. Deciding whether to get TKS depends on where you operate and how bad you need to get somewhere.

[230KT]

David,

Thanks for the numbers. That means your non-TKS Rocket is 6-8 knots below published values regardless of altitude. That, along with FoxMike's input, suggests I should expect 10-15 knots below published values for a Rocket that is TKS-equipped (and with a smooth paint job!).

[aviatoreb]

David,

Thanks for the numbers. That means your non-TKS Rocket is 6-8 knots below published values regardless of altitude. That, along with FoxMike's input, suggests I should expect 10-15 knots below published values for a Rocket that is TKS-equipped (and with a smooth paint job!).

My Rocket has a TKS install. It was installed in 1994 on the 231 before it was converted to a rocket in 1997. It was an early tks install and so it is not nearly as smooth as most more modern tks installs I have seen. I run roughly 5-10kts slower than book - so roughly 2 or 3 its slower than Davids reported speeds and power/gph settings. I also have VGs by the way. I say 5 to 10 since it seems so dependent on temps and pressures of the day as to what I actually get - call it 7.5+/-2.5 is a better way to say it. It is still a very very fast airplane. One thing about Rockets more than any of the other Mooney setups I believe is the variability of power settings available - I can burn anything from 11gph to 24gph depending on how fast I want to go. I never burn it harder than 21gph/75% but that produces some super speed, the speed value depending on altitude - my values as I said are from 5 to 10 slower than what you read on http://www.rocketengineering.com/sites/all/docs/305Rocket.pdf

I have not been above 20k by the way. As to what you see on flight aware - that is ground speed and depends on winds aloft of the day. I have several times gone 240GS going east toward Boston at moderate 15 or 17k. On the same day I would come back at 9 or 11k to try to duck below the winds which are often growing faster with respect to altitude than the speed benefit of a turbo makes you go faster. My top ground speed so far is 281gs. I know 300gs will happen someday.

Adding to what FoxMike said "I find the TKS to be useful even though it does not get used very often. I hate giving up the performance until I get into a bunch of ice. " I agree and once more I enjoy having TKS tremendously as it gives me peace of mind on all my flights and less worry knowing I have it "just in case," so I enjoy it all winter long even though I avoid ice - and in the summer - I have seen ice in May and June at altitude. It was a major feature consideration when shopping airplanes.

[M016576]

My Rocket has a TKS install. It was installed in 1994 on the 231 before it was converted to a rocket in 1997. It was an early tks install and so it is not nearly as smooth as most more modern tks installs I have seen. I run roughly 5-10kts slower than book - so roughly 2 or 3 its slower than Davids reported speeds and power/gph settings. I also have VGs by the way. I say 5 to 10 since it seems so dependent on temps and pressures of the day as to what I actually get - call it 7.5+/-2.5 is a better way to say it. It is still a very very fast airplane. One thing about Rockets more than any of the other Mooney setups I believe is the variability of power settings available - I can burn anything from 11gph to 24gph depending on how fast I want to go. I never burn it harder than 21gph/75% but that produces some super speed, the speed value depending on altitude - my values as I said are from 5 to 10 slower than what you read on http://www.rocketengineering.com/sites/all/docs/305Rocket.pdf

I have not been above 20k by the way. As to what you see on flight aware - that is ground speed and depends on winds aloft of the day. I have several times gone 240GS going east toward Boston at moderate 15 or 17k. On the same day I would come back at 9 or 11k to try to duck below the winds which are often growing faster with respect to altitude than the speed benefit of a turbo makes you go faster. My top ground speed so far is 281gs. I know 300gs will happen someday.

Adding to what FoxMike said "I find the TKS to be useful even though it does not get used very often. I hate giving up the performance until I get into a bunch of ice. " I agree and once more I enjoy having TKS tremendously as it gives me peace of mind on all my flights and less worry knowing I have it "just in case," so I enjoy it all winter long even though I avoid ice - and in the summer - I have seen ice in May and June at altitude. It was a major feature consideration when shopping airplanes.

300 GS in a single engine prop... NICE! I'm with you Erik: if you need FIKI TKS then it's a no brainer. Particularly when you look at the relative loss of speed on a rocket. It's really just a drop in the bucket for a rocket, but you gain months worth of usable fly days a year. 10kts on a J is a much bigger deal! (I'll spare my old Math prof from witnessing me attempt some public percentages! )

[aviatoreb]

300 GS in a single engine prop... NICE! I'm with you Erik: if you need FIKI TKS then it's a no brainer. Particularly when you look at the relative loss of speed on a rocket. It's really just a drop in the bucket for a rocket, but you gain months worth of usable fly days a year. 10kts on a J is a much bigger deal! (I'll spare my old Math prof from witnessing me attempt some public percentages! )

Hey Jobe - Enjoying your new jets still? I'm giving a MA514 topology exam this morning...wish you were there. :-)

One note - you misspoke because a rocket cannot be FIKI even if it is a rocket mod converted from a formerly FIKI install on a M20K 252 that has the full FIKI install. That is just a legal status as far as I understand it since the system is the full formerly FIKI system that remains intact the airframe - except CAV aero has the prop slinger mod for a rocket prop and I have that of course on my plane. (Strangely, my rocket had tks complete except on the prop when I purchased it - the owner had not bothered to put tis back to the prop?! I did that immediately upon purchase). Mine is a M20K 231 convert and the TKS install was nonFIKI in the first place. As said many times here the main difference of the tks installs is that fiki has dual pumps and inadvertent does not and dual alternators. Flow rates are identical. Dual pumps is very nice, but on a rocket I consider dual alternators not necessary as the rocket mod includes two 35amp batteries placed in the tail to rebalance after adding a TSIO520 - and this adds a huge amount of battery backup that I consider at least comparable to a backup alternator in an emergency.

As I said somedays its 10 slower - but some days only 5 slower than book - according to atmospheric differences I presume.

[aviatoreb]

My Rocket has a TKS install. It was installed in 1994 on the 231 before it was converted to a rocket in 1997. It was an early tks install and so it is not nearly as smooth as most more modern tks installs I have seen. I run roughly 5-10kts slower than book - so roughly 2 or 3 its slower than Davids reported speeds and power/gph settings. I also have VGs by the way. I say 5 to 10 since it seems so dependent on temps and pressures of the day as to what I actually get - call it 7.5+/-2.5 is a better way to say it. It is still a very very fast airplane. One thing about Rockets more than any of the other Mooney setups I believe is the variability of power settings available - I can burn anything from 11gph to 24gph depending on how fast I want to go. I never burn it harder than 21gph/75% but that produces some super speed, the speed value depending on altitude - my values as I said are from 5 to 10 slower than what you read on http://www.rocketeng...s/305Rocket.pdf

I have not been above 20k by the way. As to what you see on flight aware - that is ground speed and depends on winds aloft of the day. I have several times gone 240GS going east toward Boston at moderate 15 or 17k. On the same day I would come back at 9 or 11k to try to duck below the winds which are often growing faster with respect to altitude than the speed benefit of a turbo makes you go faster. My top ground speed so far is 281gs. I know 300gs will happen someday.

Adding to what FoxMike said "I find the TKS to be useful even though it does not get used very often. I hate giving up the performance until I get into a bunch of ice. " I agree and once more I enjoy having TKS tremendously as it gives me peace of mind on all my flights and less worry knowing I have it "just in case," so I enjoy it all winter long even though I avoid ice - and in the summer - I have seen ice in May and June at altitude. It was a major feature consideration when shopping airplanes.

I retract my 5-10kts slower than book estimate I gave my plane. My cowl flap lever broke last month. After the fix - just got it back last week - I think my plane is faster! I think my cowl flap must have been always trailing half open and now I am finally closing it. Anyway, now call my plane 2-5kts slower than book and I am still blaming my rough tks install for that. But I am pretty happy about having found 3-5kts out of what otherwise seemed like a pain in the neck repair of the cowl flaps.

[rocketman]

As physics announces, for every action, there is an equal and opposite reaction. For TKS in a Rocket, what are you accomplishing - a very occasional severe icing condition that requires the alcohol spraying a corrosive chemical all over your plane? Emphasis Corrosion!!!. For my Rocket which dies not have TKS, and no corrosion, the plane can fly through (non forecasted) icing layers with ample power to spare, going on top to sublimate what little the 1000 foot icing layer might lay on the wings. It's really not a big deal if you plan our departure at airports forecasted to be above freezing. The plane is like a giant powerful engine that will lift you through a lot of bad icing if you don't stay at those altitudes very long. Plan your decent carefully and you really don't need the alcohol fluid spraying across your wings very often. Remember, a powerful engine is worth a lot more than a de-icing system if you flight plan carefully to prevent icing on a decent in bad weather! Everything has a trade off. I'll take the speed and power over a seldom used corrosive environment to make a very seldom trip doable. If the flight environment is that bad, plan on alternative transportation, TKS or not!

[carusoam]

Rocketman,

Would an electrically heated prop add any value to your fast plane/powerful engine/no chemicals stance?

I asked Hartzell while searching for a new prop...

Best regards,

-a-

[David Mazer]

Carusoam, I don't believe you are supposed to put a heated prop on a Rocket due to the STC but I believe there are some out there anyway.

Rocketman, I don't think glycol is corrosive but I'm not certain of that. I disagree that power is enough, depending on where you fly most. I flew into icing over your neck of the woods a long time ago and it was all I could do to turn around and be out of it in 90 sec without falling out of the sky. It took over an hour for the ice to sublime sufficiently for me to attempt a landing. One of the scarier flying events.

I would be willing to carry the extra weight of the equipment and lose a couple knots in speed all the time for the few times I would need it and the many times I wouldn't go (haven't gone) because there is a chance of ice and I wouldn't take the risk. Living in Florida makes it less important but in a Rocket one can cover a lot of distance and a lot of weather.

[gjkirsch]

I think two points are worth considering. First, the increase in value to the plane is about 50% of the cost of the TKS install. So, if you want TKS, buy a plane with it already installed. Second, this type of plane woud typically be for long trips where extended weather planning is less reliable. You should expect to be exposed to icing at any phase of flight. We all like to talk about climbing through the thin layer and flying in the clear air on top, but it isn't always clear for the entire trip; and, if you plan to land or take off any where around DC, you will be held down low for extended periods of time.

[rocketman]

My Rocket does have a heated prop and was installed by the previous owner. Does it add value? Don't know. Does it slow the plane down? Again - not sure. I do know that there is no fluid I need to worry about and is always there one switch away. As far as how many Rockets have heated props? Good question.

In David's Mazer's message above, I would heed to his opinions and experiences since he know more about flying Rockets than anyone else I know. For me, I am instrument rated but do not fly in hard IFR conditions and would rarely ever encounter the icing conditions he spoke about. I guess all I need is an electric pitot and prop heater for getting out of a "little" ice. I have had bad ice build up in my 201 years ago when I was more aggressively flying IFR, and for me - never again.

I basically fly only when I need ti get over a thin layer of clouds, rarely stay in clouds, 800 foot minimums are my standards, and the temperature on landings must be over 40 degrees to prevent landing with ice if the flight is not all VFR. Obviously, I do not need my plane for my day job, and use it for pleasure only. So TKS would not be necessary for my missions.

[aviatoreb]

My Rocket does have a heated prop and was installed by the previous owner. Does it add value? Don't know. Does it slow the plane down? Again - not sure. I do know that there is no fluid I need to worry about and is always there one switch away. As far as how many Rockets have heated props? Good question.

In David's Mazer's message above, I would heed to his opinions and experiences since he know more about flying Rockets than anyone else I know. For me, I am instrument rated but do not fly in hard IFR conditions and would rarely ever encounter the icing conditions he spoke about. I guess all I need is an electric pitot and prop heater for getting out of a "little" ice. I have had bad ice build up in my 201 years ago when I was more aggressively flying IFR, and for me - never again.

I basically fly only when I need ti get over a thin layer of clouds, rarely stay in clouds, 800 foot minimums are my standards, and the temperature on landings must be over 40 degrees to prevent landing with ice if the flight is not all VFR. Obviously, I do not need my plane for my day job, and use it for pleasure only. So TKS would not be necessary for my missions.

Hi Rocketman, and all,

Ooops - sorry folks...I had not meant to open back up the "is TKS" worth it or useful debate. I was only correcting my report that TKS was slowing my plane 5-10kts - since my cowl flap repair finished last week I seem to have gained back ~5kts. So lets say now my rocket is 2-5kts slower than book. That was the point of my post correction to this thread. As far as I can tell, I am the only poster here with a tks rocket, but hardly the only mooney owner with tks. My tks is install is rather earlier and rougher than those found in the newest airplanes. So it is easy to believe it is stealing the up to 5kts - but not nearly as much as I originally posted. I am tickled to get back 5kts from an innocuous repair.

Now to the recent points.

I do not know if tks is corrosive, but I tend to doubt it. There is not a hint that it is on my airplane despite that it has been installed since 1994. If it is corrosive, then I doubt it is very corrosive. It is a very very tenacious fluid - meaning sticky - and this is how the fluid is designed - if I run it for 5 min at the beginning of a flight and fly another hour and a half - it is still on the wings when I land ,and it is still on the wings the next day.

I think there is not a right answer as to if tks is worth it for a rocket. It is a personal choice if you want it. While I hardly launch into conditions that suggest I will collect ice, there is so very very often the possibility of ice in the northeast, and esp where I live which is in the vicinity of the great lakes...it really gives me some peace of mind having it. I enjoy my winter flying that much more knowing I have it...even my vfr winter flying. And of course at altitude, winter extends from September to May...and the worst ice I ever saw was in June once over westchester county, decending from FL17. Yes I had warm weather below to escape but I ran the tks anyway that day because it was collecting pretty quickly. This was unforecasted ice, and also no pireps. Mine was the first pirep. Generally, I just run the tks when I punch up through a layer - not expecting their is ice, but it gives me a good feeling running it anyway. Lots of power and a hot prop would work there too but you do have to land eventually and nicer to land with clean wings.

Rocketman, I am curious - where do you live? Surely our view toward deice includes our environment.

I enjoy a fast airplane, but I enjoy a swiss army knife too with lots of tools and a slight compromise in speed for a very useful tool in my pocket makes me really enjoy my airplane that much more.

Oh...slight benefit to tks - you never get paint chipping of the leading edges. :-)

[rocketman]

I live in the TN-KY-VA area, near the beautiful Cumberland Gap National Park, where not only do the foothills of the mountains give us beautiful scenery all year, and fertile 80 miles of trails for my marathon running addiction, but also unpredictable weather conditions, clouds, and icing. To be honest, since the two local airports I keep my 201 and Rocket have no instrument approaches (and one without runway lights) and are linked to mountainous terrain, I feel that my flying has to be more carefully planned out for weather. I have been flying Mooneys since I purchased the 201 in 1989 and still feel like a student checking everything before each flight. Very few options are available for terrain issues on departure so nearly all my flying is day time in addition to VFR. If I absolutely have to be somewhere, I always fly commercial and waist the ticket if the weather proves predictably VFR for the time I am away.

Hangar flying is as much of an enjoyment to me as flying, even tinkering and fixing things with my AP. And I can hangar fly in all kinds of miserable weather, and even enjoy a beer or two!

That brings me to another topic for the general Mooney group. "What are your most interesting hangar conversations with other pilots when the weather is bad and your just hanging out at the airport"

[aviatoreb]

I live in the TN-KY-VA area, near the beautiful Cumberland Gap National Park, where not only do the foothills of the mountains give us beautiful scenery all year, and fertile 80 miles of trails for my marathon running addiction, but also unpredictable weather conditions, clouds, and icing. To be honest, since the two local airports I keep my 201 and Rocket have no instrument approaches (and one without runway lights) and are linked to mountainous terrain, I feel that my flying has to be more carefully planned out for weather. I have been flying Mooneys since I purchased the 201 in 1989 and still feel like a student checking everything before each flight. Very few options are available for terrain issues on departure so nearly all my flying is day time in addition to VFR. If I absolutely have to be somewhere, I always fly commercial and waist the ticket if the weather proves predictably VFR for the time I am away.

Hangar flying is as much of an enjoyment to me as flying, even tinkering and fixing things with my AP. And I can hangar fly in all kinds of miserable weather, and even enjoy a beer or two!

That brings me to another topic for the general Mooney group. "What are your most interesting hangar conversations with other pilots when the weather is bad and your just hanging out at the airport"

Here - here to hangar flying. I enjoy tinkering with my airplane too when the weather gets crummy. In fact - that is when I wax my airplane if there is nothing specific I want to do. And why just today - with freezing rain predicted, I played with my airplane instead of flying it, installing a usb power source for my new iPad mini on the yoke - and looked in on the guy in the t-hangar behind mine - who is rebuilding from the ground up an Aircoupe - you should see the paint job on that baby - I will ask permission to post - it is a sight to see!

Rocketman, I suggest you start a new thread and call it, "What are your most interesting hangar conversations with other pilots when the weather is bad and your just hanging out at the airport" Great topic.

Back to hangar chit-chat on ice - flying. I have the same policy - when I absolutely must be there on time - I fly commercial. Absolutely.

[aviatoreb]

Perhaps this is the best way to describe how I use my TKS equipped airplane. In two years of flying this airplane, and with very careful planning, I have pushed only about 15-20gal of fluid through the system, and probably 2/3 of that was simply because you are supposed to run the system briefly every month or so as a maintenance issue, and of the 1/3, mostly it is only needed for 2 or 3 min while pushing up through a layer plus priming it ahead of that.

[N601RX]

I noticed there is a mooney TKS system on ebay being parted out

[David Mazer]

Who would install the TKS system if one bought it off ebay? I didn't think Cav is allowing anyone to do installations anymore.

[aviatoreb]

Who would install the TKS system if one bought it off ebay? I didn't think Cav is allowing anyone to do installations anymore.

I just looked at that ebay listing - its a few panels and a pump. I.e., replacement parts. I suppose if they can get yellow tagged, then that would be legit.

I think the install process itself must be part of the STC - so even if you had a complete system you still couldn't install it.

[RJBrown]

My Rocket does have a heated prop and was installed by the previous owner. Does it add value? Don't know. Does it slow the plane down? Again - not sure. I do know that there is no fluid I need to worry about and is always there one switch away. As far as how many Rockets have heated props? Good question.

In David's Mazer's message above, I would heed to his opinions and experiences since he know more about flying Rockets than anyone else I know. For me, I am instrument rated but do not fly in hard IFR conditions and would rarely ever encounter the icing conditions he spoke about. I guess all I need is an electric pitot and prop heater for getting out of a "little" ice. I have had bad ice build up in my 201 years ago when I was more aggressively flying IFR, and for me - never again.

I basically fly only when I need ti get over a thin layer of clouds, rarely stay in clouds, 800 foot minimums are my standards, and the temperature on landings must be over 40 degrees to prevent landing with ice if the flight is not all VFR. Obviously, I do not need my plane for my day job, and use it for pleasure only. So TKS would not be necessary for my missions.

If the plane had a hot prop when it entered Rockets hanger it kept that feature. Most 231 after 1979 had hot props. There are a lot of 79 231s out there. Most came without O2, good avionics or a hot prop. 1980 and later were much better equipped. After 80 the changes were gradual. The only real improvement was the folding seat.