Parkzone Stinson Reliant SR-10 PNP Review

Introduction
I pre-ordered my Stinson shortly after it was announced. It joins a Super Cub LP (with floats that I occasionally use), a T-28D, and a Night Vapor as part of a rapidly growing collection. I really liked the Stinson for its incredible scale looks, and because I like the experience of a tail dragger, but wanted a higher performance/capability option to the Super Cub. I also really liked the idea of being able to add the flaps as an “option” to the kit, requiring only the purchase of an additional servo (PKZ1090), and a servo lead extension (JSP98110).

For perspective, Ive been flying since May of this year, and have logged just under 200 flights between the three planes I have. I consider myself an intermediate flyer, and have started experimenting with slightly aggressive aerobatics with the T-28.

After seeing several videos of the Reliant in flight, I couldn’t resist. My expectations were that it would fly much like the T-28 (which I absolutely love flying), and would serve as a good high performance platform for in flight video. While I wanted it to be a capable aerobatic airframe, I didn’t expect it to be at the same level of the T-28.

Because I had an AR6200 and four 3S packs on hand (two Parkzone 1800maH, and two e-Flight 2100mah), I ordered the PNP version, as well as the accessory servo for the flaps.


Out of Box Experience
The Stinson is neatly and safely packed. The moment you slide the foam out of the box, the first thing you notice is that this is a BIG bird. The wingspan at 49.6” is wingspan is quite a bit larger than my T-28.

Mine had a few sample “defects”: The red paint on the wing is a little sloppy in a couple of places, with some overspray into the white areas, including the front edge of the left aileron. The wing color does not precisely match the red on the top of the fuselage, with the wing being a little deeper red. The right fairing was a bit discolored (yellowed) on the inboard side. None of these really have any effect, and I ignored them.

[I]There should have been an addendum to the manual included with revised control throws. It was not included in my box. See below.[/B]

Assembly
Assembly of the basics on this airplane was incredibly simple, and well thought out. However, with a PNP version, you have to think a little about the order of assembly, and jump around the manual a bit (for example installation of the receiver, and flaps). The manual pretty much assumes a BNF version, and that flaps would be installed sometime after the airplane assembly had been completed.

First in the assembly is the gear. It seems to be VERY tough, with three screws holding the gear assembly on each side. You need to pay attention to how the struts mate to the bottom of the airplane. After I had completed this step, I had to loosen one side and adjust it a bit to get it right.

The manual then goes to the installation of the wing – of course the receiver has to go in first.

I used an AR6200 as my receiver, and the installation was a breeze. There is a nice clip on the top of the battery box to hold the receiver. I mounted the satellite antenna on the side opposite from the ESC.

I also departed from the order of assembly here, and completed the flap installation. Flaps were much more of a trial and error affair. While the instructions were clear as far as they went, I wound up fiddling quite a bit with which hole to mount the pushrod, and getting the control horn correctly adjusted and on the correct spline.

In the end, I mounted the servo in the pocket, and then with the flaps in the “0” position, I attached the control horn on the spline. This worked fine. Note that I had everything plugged in/bound to do the final adjustments and testing on the flaps. I tested the flaps WITHOUT the wing mounted – if you do this, you MUST hold the flap servo down with a finger, or the servo just torques itself out of the pocket. When the wing is mounted, the servo is supported from underneath by the fuselage foam as well as whatever you use to mount it.

The manual also calls for an optional servo extension wire for the flaps. In my view, this is not optional. Completing the flap installation/adjustment would have been incredibly difficult and time consuming without it.

With the flaps installed/tested, the wing can then be mounted. This is a very straightforward, and secure mounting process. Parkzone has included two types of clips to hold the wing struts – a quick release cotter pin style, and a prettier “L” pins. For now, Im using the cotter pins to hold the wing struts, but once Im sure everything is adjusted correctly, I will convert to the more attractive “L” pins.


Trimming and Flight Preparation
I’m using a Spektrum DX6i transmitter with my Stinson. I had to reverse all three control surfaces to get them to move correctly (Aileron, Elevator and Rudder.

The manual provides specifications for control surface moment – this was the most significant oversight in my PNP kit. The specifications in the manual are wrong. I spent an inordinate amount of time trying to figure out how to get the surfaces to move to the specification in the manual. Many thanks to V2rider on RCGROUPs who responded quickly with the correct throws which were included on a separate sheet of paper in his kit as an addendum to the manual.
They are :

Low rates

o Aileron : 10mm up, 7mm down
o Elevator : 10mm
o Rudder : 17mm

High rates

o Aileron : 15mm up, 10mm down
o Elevator : 15mm
o Rudder : 22mm

Flaps

o Half : 15mm
o Full : 25mm

I have not yet figured out whether I can implement two flap positions with my DX6i. For now I have the throws set at half.

While I have not yet tested CG, it is to be 55-65mm back from the leading edge at the wing root +/- 6.4mm. Parkzone set this based upon an 1800maH battery in the center position in the battery compartment. This is what I will use for the maiden.

Taxi testing was uneventful. The Stinson tracked perfectly straight the first time. Giving it a little bump of power showed that it accelerates very quickly, and when letting off the power resulted in a tendency to turn right. Once kinda cool unexpected thing was that the servo lights provide a dim orange light in the cockpit. It looks VERY cool at night!

UPDATE After setting control throws to those listed above, I took the SR-10 back out to taxi test again. Got a little head of speed up, and suddenly it veered hard left. Turns out the bushing that holds the tail wheel in place had broken. HH has agreed to send me a new tail wheel assembly, but Ive attempted repair (epoxy) myself. Not sure it will hold, but worth a try to save the Maiden day.

Maiden Flight
The maiden flight was Tuesday evening September 28th. It was clear and calm. The "runway" (a road in an incomplete subdivision) is currently flanked by 18-24" high weeds. The battery (PZ 1800maH that came with my Trojan) was set in the center of the battery compartment, and the CG was 60mm back from the leading edge. I had flaps down (half, 15mm), and was on the low rates.

On the first take off attempt I veered left once I got to full throttle. The Stinson started to lift off, and unfortunately, caught a wingtip in the high weeds. The result was a bit of a bend in the gear, but no other damage.

After checking everything out (had to reseat the battery) the second take off attempt I over corrected, and veered right, and into the weeds (soft stop).

The third time is always the charm isnt it... Attempt #3 was straight down the runway with a beautiful scale liftoff to the east. With the late day light, the red on the wing was just spectacular looking as it climbed out. Once airborne, put the flaps up, and you can actually see it "jump forward" a bit. It was quite a bit nose heavy, so I had to put in 6-8 clicks of up trim to maintain altitude. Once trimmed, I switched it into high rates. This is one very handsome bird in flight. It handles wonderfully - while it is not as responsive as the T-28, it was almost exactly as I expected it would be. It loops well, majestic is the word that came to mind. The roll rate was fairly slow, and I lost quite a bit of altitude on an aileron roll to the right. That should improve once I can speed it up a little with the CG back a little more, and less (no) up trim.

I set up a couple of approaches just to see how it behaved in the pattern, and it is very mild mannered. Kicking in the flaps on final does result in a bit of float. I have not yet mixed in any down elevator with the flaps, but that should compensate for it. Landing was smooth as silk - with the flaps in it's slow and easy all the way to touchdown. With a little up elevator, the tail settled quickly, giving steering from the tail wheel.

Rating
PRE-Maiden rating – based upon the assembly, and quality out of the box, I would rated the Stinson 4 out of 5. While merely cosmetic, the paint inconsistencies are mildly annoying. The manual could have been organized a little more logically to consider the PNP model.

Now that I've maidened the SR-10, I would rate it at least a 4.5. Its a spectacular plane in flight, and well mannered in every way. I expect roll rate to improve with some CG adjustment. I love the flaps, a very nice touch from Parkzone. While my first two take off attempts (ahem... if I can call them that) were rough, I think its just a matter of getting used to how it behaves (it is quite different from the Super Cub). Thanks to the flaps, the Stinson was by far the easiest maiden flight landing Ive experienced.

Happy flying!

Is your esc just wedged under the foam?
I used the clips you used for the receiver for mine, and velcroed the two parts of the receiver to opposite walls of the fuselage...
Using the clips for the esc allows good airflow over both sides of it.
Dave

Just in case some of you had trouble finding the instruction book, like me, you will find it taped to the back side of the foam packing box and it is easily overlooked.

Originally Posted by SumthinsFishy

Is your esc just wedged under the foam?
I used the clips you used for the receiver for mine, and velcroed the two parts of the receiver to opposite walls of the fuselage...
Using the clips for the esc allows good airflow over both sides of it.
Dave

It is... thats probably a good idea, didnt really consider that late last night

It had the same look/design as my SuperCub, which has the "black box" RX/ESC clipped to the top of the battery box.

Originally Posted by Ta152

Just in case some of you had trouble finding the instruction book, like me, you will find it taped to the back side of the foam packing box and it is easily overlooked.

That I found... but the addendum page with the revised control throws were not in the box. I did download the PDF of the manual, it does have the update included.

jc

great review I think I will have to get one of those


ford f47

Originally Posted by ford f47

great review I think I will have to get one of those


ford f47

I just saw one at my local hobby shop. It's one of the best looking scale foamys I've ever seen. And top quality.
dleep

Very cool pics especially the last one on the deck very cool angle

Installing the optional flaps, followed the instructions. Do they seem kind of stiff at the hinge line?

I thought they were a little stiff. After I cut them loose, I worked them manually a little bit - Im not sure it was really necessary, but it seemed like the right thing to do.

jc

Read mile high's posting with interest.

I also noticed couple of what you called sample defects. One was a small cut in the foam in the top part of the rudder. Other was where the rudder connects to the fuse, where some clear tape has been added. Both of which I also ignored. Anyway last week The plane did a nose over and the top of the rudder snapped exactly at that place. Anyway managed to repair and do a short flight.

Like with most foam planes, some spots have to be protected against small dents. Since the damage to the rudder, I have put some fibre tape on either side and on top of the rudder. Also covered the main wing tips.

Mile high - are you using high or low rate with the controls. I found the low rate throws were not effective. How did you find it?

I have not tried the flaps yet. I have set it to about half throw using the travel adjustment function to trial it tomorrow - weather permitting of course.

Maiden flight of my Stinson.

http://m.youtube.com/#/watch?xl=xl_blazer&v=DYttjyi4FcY

I have the plane set up with the throws set per the manual. (Aileron, Elevator, Rudder). I do use the low rates on take off, and for me they have plenty of authority for that. Usually I make a 180 turn after take off and as soon as I have it straight and level, I switch up to high rates for the rest of the flight (including landing).

For what its worth, Ive also flown for most of a flight on low rates a time or two. Its clearly more sluggish, but I can do loops ok. Rolls were more challenging, and I lost a lot of altitude in the process. Flip it up on high rates, and it rolls nicely.

Im learning more about how the flaps interact. I had them set for 25mm (full extension), and didnt like it. With them down 25mm, it takes off like a rocket, not scale looking at all, and I was always concerned about a tip stall on the first turn. Ive since tamed them down to 15mm of throw, and mixed in 10% down elevator. Takes offs are very nice now, and when I put the flaps in on final I dont get the big balloon effect. Having said that, it doesnt slow down as much as it did before, so I may try extending them to say 18-20mm and see how that does.

jc

I just got home from the hobbyshop with mine. The hinged surfaces seem really tight even after flexing them a few times. Won't that cause excessive servo draw and therefore shorten the flying time? The small servo's don't seem to have an abundance of torque to fight a tight /stiff hinge in my opinion. Has anyone cut the stock hinge and rehinged with Blenderm?

Thanks for your opinion in advance.
Dave

Saw this Stinson at the noon demo's at SEFF. Very impressive flight. I was surprised when I saw it up close and realized it was "foam". By the end of SEFF, I had one in my car and a big grin in anticipation of flying this beauty.
Enjoy your flying. cheaha bill

The Stinson has been a "go-to" plane for me now for a while. I used it extensively as my tail-dragger trainer before I maidened my Extra 300 SHP.

I still think the Stinson is one of my best looking planes in the air.

Are you planning on adding the flaps? You really dont NEED them, but they are a fun addition. However, I think if I had it to do all over again, I would have learned to fly it without them first... actually think they add a layer of complexity.

Good luck, good flying, Im sure you will enjoy it!

Jeff