The Parkzone F-27 Stryker is an amazing airplane, especially at the price.

The inherent stability and good low-speed manners of this model break the traditional idea that fast pushers need to behave like lawn darts.

I build my first Stryker from parts last year, employing the E-Flite Six 2700kv motor and 3s high-capacity Rhino batteries.  With a 6×4, we were seeing 85-90mph reliably in radar passes, and the model handled great.

I started reading about the EFL Six, and learned that you can push a lot more than the recommended max of 42 amps.  I decided to order up some 4S Rhino batteries, and build a new Stryker.  I used an Align 450 K10175A heat sink, and decided to try one of the new Turnigy 85A ESC’s that have a built-in heatsink.  I also installed a motor temp probe for the Eagletree logger.

The first flight was uneventful, until I really started pushing up the speeds.  We saw a couple of 85+ mph passes, and whenever I started flying faster than that, I started noticing some serious problems steering the aircraft.   We decided that I was going to need to beef up the airframe and the elevons in specific before flying it any more.

I beefed up the structure with carbon fiber rod, and day-glo duct tape.  I applied CF tape and thinned epoxy to the underside of the elevons, which helped quite a bit.

At this point I also got a little reckless, and installed a new prop.  I had been running with a 6×4, and decided to put a 6×5.5 on there without thinking about how much of an increase that was. 

….  and it proved to be too much.

The model flew much better with the stiffer airframe, and spent the first part of the flight just getting used to it.  Finally, I decided to ‘give it the berries’, and see how we fared.

I wasn’t sure, but I thought I saw a little smoke trail on that climb.   I did a nice long power off glide, pretty much assuming that the motor was fried.  When I throttled up again, I was astonished to hear the motor spin up.  I decided that I must have been seeing things, and did another pass.

This time the smoke trail was unmistakable.   I spun it around, power off, and landed.   The motor was crispy critters, you could smell it a mile away and it was actually melting the plastic motor mount. 

In reviewing the data, it looks like I tried to push 96 amps through the motor, and the sky-writing was predictable at that current.

Eagletree graph, illustrating abuse

 I really should have been more cautious, we live and learn.

I got one of Custom RC’s Stryker modular motor mounts, and this is a really nice looking part.  It is available with a 28-30mm head, a 36mm head and also a special 36mm unit designed for Mega motors.   I plan to use one of Hobbycity’s 36mm inrunners, although getting the model to CG will probably be a challenge.

More news as it becomes available,

- Eli

Waiting for a Horizon Hobby order to arrive

Last week I put in a little stock order at Horizon Hobby.  I order a lot of stuff from them, and after many orders I have a real good idea of how long the shipping interval is from their California Warehouse, and also the Champaign IL location. 

For the last few years it’s been my experience that orders filled from the CA warehouse get to the Bay Area in 2-3 days, tops.  If you want something for the weekend, you order by Tuesday, and you should be set for Friday.  It is important to note that this is when you use the $4.99 shipping option.

Last week, I placed an order on 3/2.  I was really surprised when I did not receive the gear by Friday, and even more surprised when the stuff from IL showed up!

I tracked the package, and noticed that the tracking had been handed over to ‘Mail Innovations’, which is a UPS spin-off.  According to the tracking, the package has been sitting in Petaluma since 3/4.  It arrived in the North Bay 2 days after I ordered it, but’s it’s been sitting since.

I phoned Horizon customer service, and I was really surprised at what I was told, verbatim by the customer service rep:

- The tracking on Mail Innovations items is ‘goofy’, and is not really useful or accurate.  This is known and understood by Horizon.

- The rep recommended that if tracking is important to you, that you should use another method like UPS.

- These Mail Innovations packages can take up to three weeks to deliver.  I asked her to repeat this three times.
When I asked her what I should do if my order did not turn up, she said I should wait another week until Monday, 3/15.

None of this is very good for the Horizon Hobby customer in California.  

We used to be able to spend $5 on shipping and get a small order out to the Bay Area in 2-3 days.

Now, we are told we should wait 2-3 weeks for the same service, and if we don’t like that we should start spending more on shipping.

I’m sure there are extenuating circumstances that caused this, but I would expect some kind of warning from Horizon either as part of the order process, or a bulletin on their website. 

Put plainly, this change, and this poor performance is not what I would have expected from a company like Horizon, especially without notification.  And, when their customer service people tell me that the solution is just to start spending 40% more on shipping, I’m tempted to start shopping around.

- Eli

Image from Horizon Hobby

I bought the micro 4-site as soon as my LHS could get one in stock.  We were locked in the middle of a long rainy period with no end in sight, and I was really looking forward to something I could use in the conference room at the office.

The model comes with the handy reusable carrying case (box), 2 of the high cap batteries, and one of the 4-port Celectra micro chargers.  These chargers are very nice, and a boon if you have lots of micros.  That said, I got one with my MsR, and I wish I had been given the option to buy the 4-site for $130, less the charger. 

Like all of the micros, setup was as easy as charging the battery, binding it to my DX6i,and going flying.  I approximated the factory settings at 30% expo and did not bother with low rates.

Charged up, and fired up, I hauled the airplane to the office, and hung signs on the doors of the conference room that said “Important Meeting!”

ROG proved to burn up too much of the available space in the conference room, but hand launch was fine.  With the battery set exactly in the middle of the Velcro strip, it wants to roll over and hover with no problems.  However, my fingers were rusty on the sticks and I could not get it to slow down enough.  I gave up before one of my wall impacts did damage.

That night, I glued the speed brakes on, and the next day I hung the signs in the conference room again.  This was much better.  You can hold the airplane just above a walking pace, and it’s very predictable.  I was amazed at how stable it was, no real wing tipping, and very smooth. 

At this point I was starting to hit my own limits as a 3D pilot, and after 2 packs and some minor damage to the nose I was ready to quit.

I’ve owned the model for a few weeks now, and I must say that I am a lot more at home in a low-wind outdoor situation than the office. I’m still not good enough to keep it in that tight, and being able to punch skyward is still an important strategy for me when I get in trouble. 

I have some buyer’s remorse.  At $169, this airplane is not cheap, and I am starting to think that the regular 4-site might have been a better choice for me.  If I had access to a gymnasium, I would probably feel different.

The solution to this?  E-Flite needs to release a version with no fancy charger and a $125-130 price point.  Also, I think that an airframe only (no electronics) version should be offered, so that one could swap the electronics from their old, battered plane to a spanky new airplane without spending the bux for the PNP version.

We beat the Winter blues with this thing, now we just need a better value in order to keep recommending it.

Since acquiring my JR X9303 DSM2 radio in May of ‘09, I wouldn’t trade it for any other TX. Except for the new X9503. Yup. That’s right, 50 model memory.

Horizon’s website indicates shipping late this month, although we all know how that works. The official JR site has yet to be updated at this time.

A couple new features myself and many many others really wanted to see got incorporated as well:

A backlit LCD display 

The ability to trigger the timer with the throttle. No more forgetting to start the &$%@ flight timer!

Manufacturers Advertised Price for the radio & 9-channel R921 receiver w/no servos is $549, $80 less  than the previous MAP of the X9303. Considering the R921 is worth $169 alone, it’s a good bundle.

Then again, not everyone sells for MAP – “add to cart” and you’ll see what I mean. I would imagine this reputable vendor should have the X9503 radio priced similarly.

The radio retains %100 of the legendary 9303 programming, which was introduced with the 72Mhz S/PCM XP9303. Naturally it is compatible with all Spektrum aircraft receivers.

Add. model memory, more features (and useful ones at that) @ a lower price.

Although I won’t be in a hurry to replace my X9303 with this upgraded model it will be quite tempting!

-Zeke

This is one of those iconic airplanes that everybody should have in their collection of Sport aircraft.  I bought mine from Porkeez here in Sonoma County, and instead of using all of the recommended Eflite parts I switched it up a bit. 

I used a Scorpion SII-3014, 1040kv motor instead of the recommended Power 10.  Scorpion motors have a very high quality look and feel to them, and they tend to be slightly higher performance, and less expensive than E-Flite motors in many cases.   In addition, I’ve had nothing but good experiences with the NA distributor, Innov8tive Designs.  They publish a handy Motor comparison chart that makes it easy to match up their motor with another recommendation.  In addition, they publish extensive propeller data charts that are very helpful.

I coupled the Scorpion motor with a Castle Thunderbird 54, Hitec HS-65HB servos, and a JR R790 receiver.

The build was a very routine E-Flite ARF experience.  I give it high marks for fit and finish, and a few negative ones in that the hardware looks a little cheap.  Be very careful with the wing fillet.  It’s plastic that has been painted on the backside, and before the bottom wing is installed, it is prone to damage.

I used the E-flite recommended throws, which are about maximum on high rates and very close to that on low rates.  I found the thing a little twitchy on low rates with the recommended 25% expo, so I bumped the aileron travel down a few millimeters, and set the expo to 30%.  It feels better to me, set up that way.

The model rolls out fast and takes off immediately- This took me by surprise a bit on the first flight.  The light wing loading is immediately apparent, and you will see in the maiden video that I needed to use more right rudder on takeoff. 

Once up, it tracks clean and fast.  Turns look coordinated even when you do not use the rudder, and it rolls in and out of 3D with a grace that I have not experienced thus far.  Aileron rolls are fast, crisp, and clean.  The model flies as well inverted as it does right side up, almost hands off. 

Landing was pretty easy, as well.  It slows down nicely, and while it’s going to take a little practice to stop wagging the wings, it’s not a hard airplane to set down accurately. I used 1500mah out of a Turnigy 2200 in 5:30 of flight, mostly WOT. Peak draw was 46 amps on takeoff, and for most of the flight I was drawing 20-30A. The motor was cool to the touch after 5:30 of spirited flight.

In short, apply any superlative, positive term you can think of regarding the flight characteristics – I have yet to find something I don’t like about this airplane. 

BTW the snap roll feature is BRUTAL at 100% throws.  On my second flight, I hit the snap roll, and it dislodged Zeke’s Eagletree logger and smacked it against the leading edge so hard it bent the pins. (!)

Get yourself an Ultimate Biplane.  I don;t know if the E-flite/Scorpion/Hitec cocktail I brewed up is the best combination, but it sure seems to work well.

Getting to Maiden it on Christmas Day with a good friend was just the icing on the cake.

Happy Holidays,

- Eli

 I hate sending radios in for service.   I say that, even though I’m told that Horizon will do all sorts of wonderful things to your radio while it’s in their care.

So, when my DX6i turned up with a broken rudder trim tab switch, I started using sub trim instead of sending it in.  I have other radios, but that is my only DSM radio.

Last week, I tripped on East R/C.  They are out of Florida, they sell on Ebay and direct, and they have a few special parts, such as the machined aluminum trim tabs I bought from them last week.  Apparently the little plastic levers themselves are typically the part that fails, so this is a functional and cosmentic upgrade.

Actually opening up your radio is not for everybody, especially if your radio is still under warranty.  The instructions that they wrote are well illustrated/easy to follow – check it out.

Broken trim tab

I am very pleased with the result.  It gives the poor old DX6i a little bit of a nicer feel, and I plan to check out their aluminum ERC roller button upgrade!

The finished product

Here’s hoping that everybody gets something they enjoy this week.  Cheers!

- Eli