I am thinking of setting up my next jet with dual receivers after having my euro go into fail safe and crash, Before I do this I would like to see if is practical for a jet and if anyone has been able to bring a jet back on only half the airplane.

This was not practical on the Euro being a delta but I have seen a big Extra come back on half the plane but the wing loading on a big extra is nothing like what it is on an F-18.

Thanks

Dave

well, you could get ACT rx`s
if one rx dies, then the other rx takes over its servo outputs.

http://www.acteurope.de/


lots to read there if you can find the info


These are used on the huge rc A-380.......so they are jet proven

I think dual receiver will not help you in case of jamming. Why you think the second receiver will not enter in fail-safe too?
If you use them on different frequencies, you have complete redundancy. I use this system on my big extra. But, of course, you will need a dual transmitter too.

AB,
I of coarse realize that in the event of a total fail safe interference issue that chances are that it would affect both receivers I am more looking to protect against failed receivers or intermittent interference from internal or external sources.

I have set up my other jets with a single receiver using an i4C isolator with 3 redundant batteries and 3 switches.

I really just want to see if dual receiver setup would even fly the plane in the event of a single receiver failure, and hear from anyone using this setup.

Thanks

Dave

Are you sure your euro went into fail-safe? What preset fail-safe settings did you have? Example: Turbine shutdown and surface Holds, or did you have some surface preset so you could really know if it was really an R/F link problem? Other problems that at times look a lot like R/F fail-safe, but are really power failure, switch..wire etc. Did you have dual receiver batteries?

Actually dual receivers wouldn't help if in fact what you have is fail-safe R/F lockup (range problems).. actually two receivers may make the situation even worse. Dual receiver batteries and a very careful range check.. will ensure no R/F link problems.
Lee H. DeMary
AMA 36099

correct me if I am wrong, but the pilots that use dual receivers are the ones that have 10 or more digital servos in their aircraft. this way, when using a dual receiver set up, you do not draw all the voltage threw 1 receiver. a few friends of mine fly IMACC and all of thier 33%, 40 % aircraft run dual set ups. again, they all have about 12 to 14 digital servos, with heavy oz touque drawing a ton of power

mark

This is the answer :

The DPSI RV Twin version is based on the DPSI RV LDO and enables complete redundancy by using two receivers, which can be automatically switched between, at your option (depending on signal quality). This means that for the first time the entire receiver station is doubly secured. A failsafe signal of the receiver is used to switch over to the second receiver in case of a failure. Thus a total of 8 channels are completely switched over and distributed to 25 servo outputs. For the first time, ALL servos can continue to be controlled in the event of a receiver failure. The system is also suitable as a teacher-student system or as a "pilot backup". A second pilot (or "student") can take over the entire model along with all control functions using his own transmitter by means of deliberate switching (or due to an interference).

In the US this can be found in the following link :

http://www.desertaircraft.com/page.php?Page=EmcotecDPSI

I though don't have 1st hand experiance>

Dave,

I have been using two recievers in my EuroSport and Acrojet for over 2 years now. The idea is similar to both full scale fly by wire airplanes I have flown in the F-16 and A-320 Airbus. Have a back up for a single point failure. I would not do it any other way for my own peace of mind.

I split the aircraft in half and cross over the ailerons and elevators. ie right aileron and left elevator on the same reciever. In the Eurosport I split the elevons and use two servos per wing. Inboard elevons on same reciever and outboard elevons on the other. It requires programmable servos to make them match perfectly. I put the throttle and gear on the same Rx in case of fail safe on that one I would get shutdown and gear down. It only adds about 2 oz weight since I would carry the extra battery and switch anyway. In the Euro it also adds about 6 oz more since the two servos are added.

I use this system on all my large expensive airplanes and jets. I have discussed and read all the pros and cons about two recievers and extra servo busses etc and this is the way I feel best about it. Why risk the multi thousand $ loss on a single $10 crystal in the Rx. I can also tell the lawyers in the aftermath I did everything possible to make it safe. Feel free to email me off line if you have any other questions.

Gary Jones
[email protected]

I have a DPSI Twin, and plan to run on 2 frequencies simultaneously. It is a big unit and not so easy to integrate into a smaller plane.

To me, running two receivers on the same channel is a solution looking for a problem. The_real_ problem is narrowband interferecence. In the presence of such interference, 2 receivers (on the same channel) with different antenna orientations helps a little (maybe), 2 receivers on 2 different channels helps a lot.

I have not flown it yet. AFAIK, there are no commerically available transmitters on the market in the US that will let you do this. This to me is just a stopgap until we get a more reliable long range spread spectrum ISM radio going.

Good luck,

I use a DPSI Twin on my big-scale Extra. Too big for my jet. Here I use a DPSI Mini with only one receiver.

MC-24 transmitters can be fitted with two HF modules in different frequencies (35 and 40MHz...). But you can't do this "at home". It transmit 2 freq on same antenna.

I use two MX-22 to transmit to those two receivers. I linked them with a cable. I only do that when are too many pilots on the field.

From a statistical point of view, using TWO Rx's doubles up the failure rate of such a Rx. So you actually increase the chances of Rx failure. At the same time you will increase the redundancy of the total system, so at the end you may be back in square one. I personally would not use two Rx's due to space and complexity concerns. I have saved my last Bandit by having two batteries and two switches. Remember, look at the highest failure rate and fix that problem..

The question was: are you able to fly a jet model with half the controls. I think it would be very hard if not impossible to do so due to the flight characteristics of our jets and the heavy wing loading.

To increase your reliability, test all components in a prop model and after, say 10-15 flights, put the components in your jet. This is like doing your own burn in!!!

I have never tried the dual Receivers on any plane of mine but I can certainly see where you really dont accomplish anything by doing so.In fact like a couple here said it stands to reason that in essence you are doubling your chances of a potential RX issue to be introduced

I too feel that dual batteries & dual switches is very cheap extra insurance on any jet ,you can find the room needed for just one more battery & the slight bit of added weight is minimal for the extra security.My new Kingcat has 2- 6 volt 3800 mah RX batteries & 2 of the" perfect switches "into seperate channels.I feel 100% safe in saying that I wont lose any of my jets due to battery failure atleast.My ECU battery is a 3800 MAH as well.My Super Bandit and all my SM jets share the same battery setups all the way around



Steve