Hello everyone,

Just wanted to drop a quick note about our PD-1 UAS and of course to hear your opinion about it. As some of you may already know we are a Ukrainian-based company that develop and produce our own UAV systems and payload. We've been working for a while to develop and start a mass production of our own airframe and payloads. And after that spent even more time trying to put it all together. Please welcome new player on UAV arena - PD-1 Unmanned Aerial System

PD-1 UAV is a fixed-wing 3 meter wing-span unmanned arial vehicle. It is equipped with gyro-stabilized gimbal with EO and IR sensors and photo camera for aerial photo mapping. There is still enough space for additional payloads, such as radio repeater, LIDAR or any other custom options. 

One of our achievements is that PD-1 UAS is currently on service in Ukrainian Army. It is positively rated by officials and it has spent hundreds of hours in actual military operation. Our UAVs were operated in conditions where GPS/Glonass and control signals were jammed by Electronic Warfare Systems and still successfully completed their missions. Based on our experience and feedback from military operators we continuously improve our unmanned aerial system and add new features. 
PD-1 is capable of staying in the air for more then 5 hours with maximum payload and fuel capacity. This is while using regular 2-stoke engine without any modifications. We can greatly extend flight time if we add on-board generator and Electronic Fuel Injection. Service celling is 2000 meters. Telemetry datalink works for 85+ km and send all information to the ground. Including fuel level, engine temperature, outside temperature, battery status, etc. We develop whole sensor system from scratch to ensure that operator has all information from the UAV. Real-time Full HD video reception works in 50 km range. PD-1 UAV can stream video to multiple GCS or portable terminals. This means that different groups of people/operators can receive video and other information from UAV in real-time. 
USG-212 gimbal is equipped with Full HD Sony sensor with 30 x optical zoom. Which allows it to be operated on altitudes above 1000 meters and easily detect objects. Thermal camera allow to use gimbal during night time or low visibility conditions. USG-212 can be installed not only on UAV, but also on helicopters or small manned aircrafts. Here is some video from USG-212 recorded on GCS. What is actually remarkable is that Ground Control Station that recorded this video was 37 kilometres away from the UAV, so it also shows the capabilities of our video link system. 
That was only a few things that I wanted to share with you guys. And by the way PD-1 airframe itself is available for integrators and enthusiasts to develop their own projects. If you have any questions or there is anything more you'd like to know or see about our system please comment and we will share more information and content with you. 
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  • Hi John, for any price related questions please reach us using contact form on the website www.ukrspecsystems.com/contacts/

  • HI Jacob,

    very nice plane, what is the approximate price of such uavs?

  • Very nice footage!  What kind of FC you are using?

  • Hi Rob,

    Decades ago with outboards as I already mentioned and Go Karts, 2 stroke tuning consisted of milling out the port volumes larger, increasing compression, larger carburetors, modifying the crankcase and crankshaft for more volume of fuel air transfer and fancier reed valves on the intake and possibly bore and stroke.

    Actually fairly easy to double the horsepower, however at huge expense to longevity and even worse fuel mileage.

    Seized and blown apart engines were normal, not the exception.

    The best were the Austrian Konigs because they used steel that could actually handle the heat at least for a little while.

    Now it's the Japanese and the Swedes who use the good steel.



  • Chris, I agree completely. I won't let a 'tuner' motor within 10 feet of my UAV's.  In my previous life I was a Ford Powertrain engineer, and I was also involved in amateur racing.  The whole 'tuner" scene was a complete joke.  There's so much snake oil in this market.  For example, the link you provided, 6+hp from a 26-30cc Zenoah, completely BS.  He's TRIPLED the power output?  No way.  He just made the numbers up.

    These guys also claim to "balance" the engines to run smoother.  They claim they are perfectly smooth.  They fail to realize that it is impossible for a single cylinder engine to be perfectly balanced.  You can get the primary balance right, but secondary balance is not possible.  It's a geometric problem.

    I also agree, better to run a larger engine to get power, rather than a tuned one.

    Paul: What I mean is, what parts did they actually change?  Last time I asked, I was told the carb is the same, and the timing is the same.  I don't think the port timing changed.  So... compression ratio?

    Gary, yeah, you present a good argument.  Really, it would have to be decided in a proper UAV engine test and development project that I don't have the resources to undertake. In the meantime, the Zenoahs just work.

  • Hi Rob,

    Not sure I agree with you relating to sleeve bearings and oil mist.

    Lubricants have gotten very exotic in the past few decades and sleeve bearings can actually be better than ball bearings in an engine with a decent lubricant.

    I know it is a bit old school, but the simple reliability of a relatively slow 4 stroke can easily trump the much more hostile environment of a high performance 2 stroke. 

    I used Mercury 2 stroke racing motors in outboard pleasure craft racing years ago and they were great right up till the time they spit their internals out the exhaust.

    The 4 stroke Hondas that everybody uses now aren't as powerful but are about a hundred times more reliable.

    Chainsaw or not, two strokes are all over stressed in every way imaginable.

    Port timing is how you increase performance on 2 strokes and their biggest problem is shedding heat, so liquid cooling makes it a lot easier to really up the timing for maximum performance.

    Also, that is something internal to the engine based on the way the crankshaft and sleeve ports interact with each other, so it isn't something that can really be "tuned".

    My guess is that if you did some research on modern synthetic lubricants and additives you could find one that would work in that Saito for literally months on end.

    Their big one seems to be a bit heavier built than their smaller ones.

    I generally think that even a mediocre 4 stroke can grossly outlast any two stroke even the exotics like Husky and Stihl.

    I've had to get my Husky's fixed many times now, albeit, not my Stihl.



  • Look here for modified Zenoah motors claiming use for UAV.  Again, afraid to run "tuned" motors in a professional application.  I'd prefer a heavier more efficient motor running happily at constant power than a tuned, bored, ported, stuffed crank, piped motor screaming it's head off.  I feel confident trading the weight and complexity of an airborne water cooled system for larger displacement would be a better solution. Too bad there isn't a 50cc EFI equipped gas twin, four stroke, double spark in boxer configuration ready to plop in your heli.

    ZENOAH | 3D | UAV | ENGINES | GT80
  • Rob, the power difference to the marine series is due to the (much) more efficient water cooling that allows the engine to be made to deliver more power, guess it will have bigger carbs and probably higher compression rates

  • Rob, I highly recommend giving RCV Engines a call.  They're located in the UK and have been making quite impressive motors for a very long time.  I used to sell their rotarys and compact 4 stroke nitro motors some time ago and was very impressed with performance.  I know they've been working hard on developing commercial UAV engines for both fixed wing and rotary.  The web site is a bit out of date but who knows, you might get a lead if you give them a ring.  Very helpful bunch over there.

  • 3.5hp would be plenty, the Zenoah only makes 2.0.  My next build would likely use the G32RC which makes 2.4hp.

    I've also considered using the Zenoah marine series of engines, which make significantly more power, I think up to 3.5HP from the same size.  I would love to know what the difference is, but nobody really knows.  Is it the carb?  Timing?  Dunno.  However, the marines use liquid cooling.  Certainly doable to set up closed loop cooling, but it is extra complexity.

    The Saito's are nice hobby motors.  I actually have a few on planes.  But I would never use them on UAV's.  Sleeve bearing on the conrod with oil mist lubrication.  No way.  Similar, poor lubrication on the camshaft, etc.

    The Gaui GX9 UAV Heli uses a 50cc gas 4-stroke motor.  But it's also journal bearing with oil mist lubrication. No way.

    One engine I'm really interested in is the Honda GX35. It's a Honda.  And it has oil bath lubrication (I don't think it's pumped).  But it's only rated at 1.3hp.  I'm sure that could be improved quite a lot with a bit of work.  The engines are used a lot in SAE Student Competitions like the Hypermiler.  But, it becomes a development project I don't have time or money for.

    Realistically, a 2 stroke, while being technically not efficient, are easily capable of providing very long duration.  My gas heli could be made to fly 3-4 hours no problem.  What more do you need?

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