I recently purchased a TAM F 18 from a fellow nearby. He had flown it over 30 flights with no radio or engine issues. It came with servos installed and ready to fly less an engine/rx and batteries. I installed my Wren Pro 160 turbine which I had approx 5 flights on in a Boomerang with no issues. I installed 2 4200 ma NIMH 5 cell unregulated batteries to run the rx and servos and a brand new never been flown) JR 1221 rx with 3 remote rx's which I installed in more or less the same locations that he had his 3 remote rx's. All batteries were charged and the preflight range check ( engine not running) was more than double the suggested minimum in the JR manual. I normally make an engine running range check as well on a new airplane but I failed to do so on this occasion. I plan to do that in the next day or two. I have never seen much if any range decrease with engine running in the past with this radio. Prior to the flight I had run the engine and shutdown the tx to confirm that the failsafe (engine shutdown) was working, and it was. Unfortunatly the ECU gives the same message for a normal TX commanded shutdown as it does for a failsafe commanded shutdown.

As you can by now guess from the subject line I had an inflight engine shutdown while still climbing out on approximate runway heading. Fortunatly I had attained 100feet or more of altitude and was clean with a fair amount of speed when I realized the engine was dead. Also fortunate was the fact that I was flying off a giant parking lot with virtually unlimited asphalt and no obstructions. I was able to turn back 180 degrees and land down wind with about a 20 mph tailwind. Used up a ton of room but did zero damage other than nearly wetting my pants and probably over speeding the tires. When we got the airplane back to our pit area I plugged in the data terminal and the message was "Normal Shutdown" which is the same message you get regarldess of a failsafe situation or a normal tx commanded shutdown. At this point I stupidly shut the airplane off without having checked rx perfomance with the little spektrum/JR device. I then did another engine off range check and it was the same as prior to the flight. I have since then restarted the engine and it is fine.

At this point I am opertaing under the assumption that I had a radio hold and that the engine shut down from failsafe.

I am interested if anybody has any other ideas or suggestions as to what might have happened and or what to do or try next ?

I plan to do some more extensive range checks and check the data log and see if that reveals anything of concern and I plan to do an engine running range check also.

I will also add that I have several of the wires that connect the remote rx's running in very close proximity to multiple servo wires and or engine related cables. This was of some concern to me prior to the flight but it is my understanding that 2.4 gig is WAY WAY less suseptible to outside noise sources and interferance . The remotes them self and the remote antennas are well clear of any of these possible noise sources. Having said that I do have the most forward remote rx in semi close proximity to the retract air storage tanks, (metal).

Since you had shut the radio off before collecting data from the ECU or data log, it would be hard to figure out what happened. One thing would have been to seen if there were any bubbles in the fuel line before de-fueling.

Hi

Glad you saved the plane.... I also own a F18 and this is not an easy task.

Did you noticed a white smoke coming out of the turbine when it stopped? Was the UAT full after landing?

Wren uses Gaspar fadec, if it was a fail safe shut-off, the message should not be "normal shutdown". I used to had a Merlin 90 (same fadec), but don't recall this.

From your statement, you don't mention anything about the fuel circuit, so it is hard to say.

Once a plane flying with a Merlin90 crashed because the electric cable of the fuel valve was broken. The fuel valve is NC.

Maybe valves are the same as Merlin as well, because Wren does not manufactures valves. If the valve cable is cut in flight, the message should be "normal shutdown"

Among other thisngs, check your fuel valve....

Regards

Nuno

The Pro engines use a Projet ECU, very different to Gaspar's ECU.

We are guessing here but I have seen two other potential causes.

Not long ago, I was having the same problem, though fortunately the engine was shutting down on taxi out, not on takeoff. Turns out that I had to retrain the ECU to recognize the proper cutoff and idle pulse widths. I had previously trained the ECU and had a number of successful flights so I am not sure why the ECU lost the parameters, but that was the problem.

Also, if you weather conditions were cool and dry, this may have been a static shutdown, particularly if you saw no white smoke. Typically, if the engine shuts down from an air bubble or other non ECU commanded event, you will get vaporization of unburned kero. If it is an ECU commanded event that closes the solenoid, no white smoke trail. Having said this, most ECUs will have a message something like "power fail" that signals an anomaly like a static induced processor interruption.

Good luck in trouble shooting your issue.

Correct. Projet Hornet ECU. There was NO smoke. If it shutdown from a bubble I doubt the ECU would say normal shutdown, atleast I hope it wouldnt.

Pretty sure the ECU does not need to be retaught as I had just done that a few days prior and I can see the pulse width numbers on the data terminal and they all look logical. Around 1000ms for shutdown, 1200 or 1300 for stick low and trim high (normal idle) and 1900or so for full throttle, but I will recheck them just incase. There was no smoke, our weather was approx 65 degrees that day and the humidity was quite low. I would hope the ECU would have a different message if this was the cause.

If you want to get the failsafe indication from the ECU when there is an actual radio failsafe event, the RX has to, on failsafe, take the throttle channel to a signal that is well outside the "taught" range. Most of the JR guys teach the ECU with something like +/-50 or +/-75% travel to permit this... First, go into the failsafe screens on the ECU programmer box, and enable "real" failsafe (see the ProJet manual) .. I believe Ron ships them to just shut down which is simpler and safe + ama legal but you can't get the failsafe indication.

Set your travel to something less than +/-100% (like 50 or 75), then do the learn RC on the ECU. Then, set the throttle and trim low, with the ECU monitor box plugged in, go back to the throttle channel travel screen (sorry, not sure what JR calls it) and start in increasing the travel "past" (or below) low idle ( a higher percentage). At some point, maybe 100% or more low travel, the ECU monitor will show the failsafe indication. At that point rebind to make that the failsafe setting. Then go back to the percentage you taught with. Now if you get a real radio falisafe, you'll get a failsafe shutdown message vs. a user off which does not distinguish the reason.

I hope this makes sense, since I am more of a Futaba guy I may have bungled the JR terminology.

I have lots and lots of flights on Wren 160s with Projets and it works very well.

One other thing to consider, but maybe a little "out there" is that there have been some reports (not on Wren, but I think everyone uses the same solenoids) of bad solenoids, that do an uncommanded close while the engine is running. This causes the stop with no vapor symptom, but in this case the ECU shows "LOW RPM".

Good luck and hope this helps. Ron Ballard has awesome customer service and I am sure would be happy to assit you...

A JR guy may want to chime in here, but isn't there a default setting on the JR systems where the throttle goes to "full low" .. I presume if not explicitly set by rebinding?

Dave

I use the Wren 120 Pro with the Projet III ECU. Splendid combination. BUT. I made this mistake myself once, so this may have happened to someone else too:

1. Normal shutdown with throttle low, trim down until turbine stops.
2. New flight. I forget to raise the trim-but the turbine starts anyway with the throttle stick ...and it shuts off mysteriously while taxing. Luckily not in the air. DOH-a new start and now with trim up...

Do You use flight modes? Well, don´t include the throttle in them because...

1. Normal start with flaps up
2. On the final with full flaps-shutdown. Why? Because sometimes we taxi back with flaps still down and if the shutdown is done then, the flight mode remembers this mode for a shutdown...


Tuomas

Not saying this is the reason your shut down, but may contribute to the disscusion, I had an idle up setting on the UC switch for my JetCat but had not noticed that the idle up also moved the high throttle curve outside the ECU learnt limit, so take off normal, select UC up instant shut down, good job it was in an Elan, quick 360 and landing without any problems. The Futaba 12FG's latest software update has an idle up facility that only operates on the low end of the curve, I don't know if JR Tx's do something similar?

Mike

I bought the wren cable that goes from the ECU to to USB lead and downloaded the software too. It lets you download all the parameters from the last x minutes of flight (50 minutes rings a bell)
I have a supersport bought about three years ago. Might be worth contacting Wren, to see if its available for your version of ECU.

It would at least let you know definitively where your ECU thought your transmitter position was.

The same thing happen to me twice on a Wren 44, after the first time I thought it might of been a battery and since batteries start dieing the ESU's do funny things so I replaced the battery. Then took it up for another flight same thing happen turbine shutdown and I landed safely. So I looked even further into the fuel system and found that the pump motor was dieing on me replace the pump and all is good now. Check you pump, use a 1.5V battery and see if it is pumping fuel at that voltage.

since you got a normal shutdown, the ecu was commanded to shut down. otherwise it would show the error on the projet. Since it didn't smoke, it had a normal shutdown, so it somehow saw the low throttle pw.. Since you were at a high throttle setting, it would not matter if the trim was up.

On the projet, you need to make sure it goes to Auto HC after start to enable any failsafes...

It very much sounds like you went into radio failsafe. Since you tested it go OFF when you turned the TX off, that means you bound it that way correctly, so it simply thought it received a cutoff command just like normal..

Start with the receiver... pull it and send it in along with the sattelites, and if you have time, send your transmitter in too to have it checked... It is possible your receiver was not working correctly since your interference was higher. It is also possible that your Transmitter may not be 100%

Another option first is to bind it to A DIFFERENT Transmitter and check the radio against yours in the same location..

Im glad you saved it. I would consider moving to a 1222 receiver with 4 satellites for that caliber of aircraft... I think it has the best overall reception of any JR receiver.

you must always relearn transmitter when anything is changed. I wonder if it went out of range..havent tested that... see previous post for my thoughts

Im pretty sure my TX is fine. I fly over a dozen different aircraft with this one tx. Infact, shortly after the f 18 flight I flew my BVM F 86 turbine with no issues and it only has an AR 7000 or 9000 rx.. I do agree with your assement that it was in all likelyhood a failsafe situation. I am not sure what you mean by "out of range ". I was no where near as far out as I normally fly so it SHOULDNT have been out of range if thats what you mean.

Does your ECU have different indications for shut down? "Fail Safe" "Rx off" "Normal" or "Low Trim" or some such, the difference between fail safe and a commanded shut down will certainly be indicated in the GSU screen for last shut down, at least that way you could eliminate the Radio gear and look to the turbine installation.

Mike

And now for the rest of the story. Today I installed a differnt rx and remotes from one of my other planes that I knew worked fine. Repostioned slightly a couple of the remotes and went to the field. Did an engine off range check while my helper spun the airplane around the entire 360 degree circle. Found in all orientations my range check was at or beyond the 90 foot minimum. Infact in ever orientation but one it was proably 50% greater than the minimum EXCEPT when the tail of the airplane was pointed directly at me and me directly at it. In this orientation I only had a few feet more than the minimum and this was about exactly the way it was orientated inflight on the first flight when the engine shutdown. We experimented for a while with diffenrt postions of two of the three remotes and found an setup where I got a 25 % or so beter range check with the tail pointed directly at me which still wasnt as good as the other orientations but was a noticeable improvement. We then did and engine running range check and it was only a few feet worse than when not running and still well over the minimum so it was time to fly. Made two flights with no holds. I cant recall now for sure but I do think it did show two frame losses on the first flight. The flights were totally uneventfull and seem to cement in my mind that I did infact have a hold and a failsafe shutdown on the first flight. I think ultimately I might try to relocate one of the remotes in the far rear end of the airplane and see if that improves my tail in range checks. I will need a much longer wiring harness to accomplish this and I will need to find a relatively cool (temp wise) location.

Super!!
see my PM ..

HAving frame losses is normal Having HOLDS is not.. I have seen many flights with a few frame losses..

The beauty of the checker is that you learn the normal counts, and when something goes up unexpectedly, you can diagnose. Happy flyin!! its too damm cold up here to fly.

PM me your contact info, I get to Ft Worth often.. thats my stomping grounds..

Generally speaking, you can move one of the antennas out in the wing root and get the same effect if you get it out far enough as putting it rearward.. 36 inches is the max cord length.. Longer would work because its a digital serial link, but no need to push it. I would also put one as far up in the nose as possible. It will be your best receiver 95% of the time, until tail on.. then the wing root one will get you covered. I usually put them in each wing root, one in the nose, and one in the belly. with the 1221, I skip one wing root. with jets, always use the max number you can plug in. its cheap 30$ insurance.

Brian, glad you got it sorted out! Iwaived off my trip to TMS yesterday, looked a little gusty.