Viability of sharing a turbine between 2 models..
 

Title pretty much says it all, how viable is it to share a turbine between 2 different models. I currently have a Jetcat P140rx and a Kingtech 140G. I recently ordered a Sebart Avanti with the 140 sized thrust tube option. I fly my jets mainly at Jet rallies and I don't think I'm likely to fly all 3 models the same weekend so I was considering simply buying a new ECU, fuel pump and wiring harness for the Avanti and swapping a turbine out of one of the other jets. It seems that will probably cost about $700 for the ECU, etc which is about 1/3 the cost of new Kingtech 140G. Is swapping these things around really as simple as removing 4 mounting bolts and swapping over the electrical cables and fuel line or am I asking for issues that I simply haven't thought of yet?

In my opinion, it is an easy process. Not only do I move the turbine, but because I am so cheap, I also move the electronics for the engine and the UAT. Usually takes about 90 minutes for the transfer.

The only issue I can see is keeping the time on the turbine. Its not so much of an issue with the Jetcat, but if the Kingtech has a mandatory 25-hour service limit then you'll have to take note of where the total runtime on the turbine is stored. I'm fairly sure that on the Jetcats its stored in the ECU, so you'd have to add the two times together to determine the total run time. I don't know about the Kingtech.

Bob

Good point, I hadn't thought about that. I suspect both the Jetcat and Kingtech store the run time in the ECU.
Also, when you order a turbine, are internal ECU values such as fuel pump voltage, etc, factory adjusted by test
running that turbine / ECU pair? If I order a new ECU will I be able to simply copy these values from one ECU to
the other or do they typically ship with default values?

Another good thought. Not only would it save money, it would eliminate the issue with maintaining the run time of the turbine across 2, ECUs and any possible "tuning" issues as well. Unfortunately, even though I'm pretty cheap, I'm also pretty lazy, not sure which will win out here.... Since I'm thinking I may end up swapping the turbine 3 or 4 times per season, I'd really like to keep the swap out to something in the order of 15-20 minutes...

at my field there were quite a bit of guys that were doing the SWAP
since engines have come little more down in pricing they since have individualized each jet with turbine
i know one who was swapping mammoths with just a 4 bolt process and took 10 minutes to line
up
he too has since gotten another engine
he didnt want to deal with any issues of owner error or mysterious thiings that may compromise performance

It should not be a problem but make sure you keep the ECU with the turbine. So since its a G all the valves are on the turbine and stay with it. You asked about the valves and if they are matched to the ECU. They are just open and closed valves and any valve will work with any ECU.

The only problem I could see is if the fuel systems are allot different and one has more suction then the other you might get a starting problem. But it would have to be a pretty big difference to hurt anything.

Ok, I had hoped to have a second ECU and fuel pump so I wouldn't need to swap it between jets, just unbolt the turbine move it to the new jet and reattach the fuel lines and wiring harness. If I really need to move the ECU as well that makes things a bit less desirable but since it tracks run time, etc, it make sense. What about different fuel pumps? Does the pump voltage need to be tweaked to get the proper fuel flow, etc, between 2 different fuel pumps? I really would not want to need to do any kind of tuning each time I swap the turbine / ECU..

With the new Jetcentral system, this is very easy to do. All the information is kept inside the turbine so you just need a couple of power packs (connection box with the fuel pump and the valves to have a clean installation) and you are done.

The PowerPack has the following:
Fuel pump
Solenoid valves
Electronics to control the power to the fuel pump Electronics to control the valves Electronics to comunicate to the HDT (s-bus) Electronics to comunicate with the turbine internals (s-bus) Electronics to read the pulses from the receiver Electronics to monitor Battery voltages

The electronics under the front cover has the following:
RPM sensor
Thermo coupler input
Electronics to control the power to the burner Electronics to control the power to the starter Main processor (the brain) Data storage (timers, operational parameters, data log, serial number)

There are two different Sizes of PowerPacks, one for the large engines (mammoth and Rhino) and other for smaller engines (Rabbit and Chetah) The main difference among both is the size of the pump and the flow rate of the valves. (electronics are basically the same)

PowerPack can be replaced and no programing or parameter changes are needed, because all info stays with the engine.

This sounds like a very well thought out system, unfortunately, I don't currently own one of those so it doesn't really help with my current situation. Still it sounds like a very good selling point for guys like me that would like to share a turbine between models..

I was actually considering the same thing recently. I was thinking on getting the wiring harness and pump. simply unplugging the ecu and engine. Fuel system would be close to identical in each plane. Pull the engine and ecu and reinstall. Make a couple connections and done. Less than 30 minutes.

The JetCat you have keeps the runtime inside the turbine not the ECU. If you swap with the proper electronics you don't need to do anything or adjust anything just swap the turbine.


EDIT: You DON'T have to keep the ECU and the turbine together. Just to clarify. This might be for a JetCat only, I don't know if anyone else is different.

Pumps can stay in the plane. So buy a pump. But you need to keep the ECU and turbine as a unit. Not sure about your access but should be a simple swap.

I have done the same with my PST Reaction and Avanti S. Just swap the turbine and ECU. Get an extra pump and cable harness. Avanti fuel tank will have to come out to fit turbine. PST Reaction very easy swap over.

Like others, swap turbine and ECU. Make your ECU installation easily accessible (Velcro is your friend!!!).

No need to have a turbine sitting there without use. Swapping turbines is a 10-15 minute job if your installation is properly planned. It gets a little more complex if they dont use the same mounts (for example, bypass vs rails), but that adds 5 minutes more at the most

Good thread. I may lean the way of turbine + ECU based on what I am hearing. Little bit cheaper that way too.

I'm running a Wren 44 Gold between 2 airframes each one has its own pump/ecu/harness and the turbine exchange takes less than 10 minutes (couple of plugs and a fuel line plus 6x M3 capscrews).
It's a simple matter of adding each ecu's runtime together to get total engine hours for maintenance purposes.
Just could'nt justify a 2nd turbine for 2 of my smaller jets that don't get flown that much....works out just fine no issues and cost effective!

I personally would never swap turbines around as for me it adds an extra risk factor that I am not willing to take with my jets,just my 2ps worth.

I have two IQ Hammer 170's and three install kits. They are all "swappable" between any of the install kits and the turbine history and parameters are all stored in the Turbine. All you do is plug in 2 wires and one fuel line. I keep a stock of the festo plugs and caps so nothing can get into the fuel system or leak out. The most time consuming part is undoing the mount...

Seems this is the general direction things are going with the electronics. I'm just waiting for an interface from the ECU to the futaba telemetry so I can use the transmitter screen for the GSU functions.

PaulD

This probably will subject the ECU of having to "relearn" the new air frame, ie. new pump, difference in fuel restrictions....etc. could be problematic upon start up, since fuel delivery at that stage being so finite. Then again, if you are thoroughly familiar around the ECU and don't mind the challenge, maybe worth the trouble.

Regards,
Barry

As Matt has said, JetCat's are designed to be swapped around from airframe to airframe they even sell an installation kit for that very purpose.

Mike

Wayne!

I swapped turbines between two jets for several years. I had both jets set up the same, and just swapped the engine. I had two complete set ups, ecu, wiring harness, valves, pmp, UAT, etc. Just switched out the turbine. On some jets, it is extremely quick and easy, others jets, it is a hassle. It is the most reasonable way to have more then one airframe with one or two turbines. Good luck!

With planning & some room it could be very simple.

If you could mount the pump, solenoids, filters, ECU etc on a single plate in the model
you could lift the whole shebang out as a unit, connect radio leads, fuel lines & battery
& off you go. Sort of like making your own Jet Central Powerpack.

The bad news? - you will have to modify 2 models, your existing & your new one.
The good news? - you won't have to spend anything!

Yes, Velcro will be your friend. I don't know if any peculiarities of air flows or pipes
will mean any parameter changes are needed. - John.

I would consult Kingtech , I was told by king teck that two ecu's was not recommended and that would void my warranty.

J.C

I have a P-100RX that I use on a F-16 and my Blanik. The RX engines make it easy to swap turbines. As a matter of fact, I swap the turbine, ecu and pump. The reason I do the pump is because the RX engines have pumps that don't have a fixed lead on the back. The lead plugs into the back of the pump making it easy to pop out. I got JC to send me the wire harness, an i/o board, mount and some fittings. It cost me $280 and now I double the use of my P-100. I can switch it over in less than 30min. Just buy some extra festo caps to seal off the fuel lines when the turbine is removed.