Newbie father/son seeking assistance with Hobbico Park Pilot

My son and I were given as a gift a Hobbico Park Pilot RTF, even with
an extra set of wings and multiple extra props. I have absolutely no
experience with these airplanes or any type of remote control
models....total newbie, but my son and I were looking forward to the
potential for fun.
My son (6) and I enjoyed the little bit of set up required, and today
we took it for its maiden voyage, even though winds were a bit greater
than ideal (10 mph). Well, needless to say, we crashed after a nice
(but short) maiden voyage, and the propellor got jammed in the turf. I
was unaware that I should have immediately shut off the
throttle....perhaps it stayed like this for 3 minutes. We had to
replace the propellor, but upon making this repair, now the motor will
not work properly.
Following the "turf-jam," the symptoms of the motor problem are that
even with a fully charged battery, the motor won't stay on. The motor
comes on only with the red button on the side of the plane depressed,
and held depressed. As soon as I let up on the red button, the motor
shuts off. The throttle control still will modulate the motor speed;
however, the motor only runs as long as I have the red button
depressed. Also, the motor sounds as though its maximum RPM is a bit
lower than before.
My (totally uneducated) guess is that I damaged a component in the
receiver. Here are the specific components:
1) Hobbico RX-405 AM 4 channel receiver: Futaba R114H 72.670 MHz (it
reads "44" above the marking for 72.670 MHz). (The little piece that
pulls out of this box is labelled "Type 72-11 AM Rx" and also labelled
"44"
2) Ni-MH battery: 6 x AAA 650 mAh
3) Motor: GFK-180SH-2860
4) Radio: HObbico 3 Channel AM Radio Control System by Futaba 72.670
MHz (Came with the Park Pilot)
Here are my questions:
1) Do you think my "diagnosis is correct," and if not, what do you
think is wrong?
2)Is there a way to repair this unit, or does it need to be replaced?
3) My son and I are really bummed...what part should we order to get us
flying again? I searched the internet for this 4 channel receiver, but
there are so many specifics that one has to specify, that I'm afraid to
buy anything. "High" versus "low" "with crystal" versus "without
crystal"
Thanks very much for your time and thought.
-Ken and Brian
Reply to
kkt_mag
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Before pressing the red start button, is the throttle control on the transmitter all the way down (to the off position)?
Reply to
aeropal
The 44 is the channel number for 72.67MHz. The FCC has assigned a number of channels in the 72MHz band for model aircraft radio control.
There is a speed controller in there as well, I suspect as a seperate part but possibly as part of the receiver as a cost-cutting measure. I don't know about the little RTF planes, but usually a speed controller has a low battery cut-out circuit and the better ones have overcurrent protection as well.
In order of likelihood here's what I think happened:
a. You fried the battery pack. This would cause it to not be able to deliver enough voltage to the motor under load, and the speed controller would cut the motor off unless it's being reset. If you have a voltmeter and quite a bit of manual dexterity you could measure the voltage to the motor under load and full throttle -- it should be around 6V with a freshly charged pack. Failing that the cheapest way to test this on your own would be to replace the pack and see if it fixes the problem. If you can visit a local hobby shop (see below) they may be willing to cycle the battery for you & see if it appears to be in good condition.
b. You bent the motor shaft. This would cause the motor to run slow and draw too much current which would either pull the battery voltage low or cause the speed controller's overcurrent limit to cut in. If it's a direct drive setup you should be able to see that the shaft is bent, particularly if you run the motor without the propeller. If the thing vibrates excessively or if you can just plain see the bent shaft then that's the problem.
c. You munged the gear box (if there is one), or the motor. This would cause similar problems to the above. If there is no gear box then the motor should spin quite freely -- if it doesn't then you probably jammed something inside the motor or much more likely broke a motor mount and now have something rubbing that shouldn't. If there _is_ a gear box then you may have bent a shaft or broken a gear. Rotate the prop by hand and see if it feels fairly free. The right feel is hard to describe, unfortunately.
d. A very distant 4th place would be that you did damage to the speed controller itself by overcurrent. I doubt this is the case, though.
At any rate, I don't think the damage would extend beyond the motor, battery and speed controller.
Does Hobbico give you any parts lists, and are there any numbers that you can call or web sites you can visit to order parts?
It may be worthwhile to find a local real hobby shop (_not_ KB toys!), bring the thing in and see if they'll help you. Look for a place that seems to be staffed by folks who actually fly model airplanes. Even if they can't get the thing going for you they should have better RTF and ARF (almost ready to fly) airplanes to replace it. If they are helpful then be sure to reward them with your business when you want to get a second model or accessories for this one.
You may also want to see if there's a flying club with someone willing to train you. You _can_ learn how to fly RC all by yourself, but you learn quicker and go through fewer airplanes when you get help.
Good luck. Flying RC is a bit of a skill, so you'll need to persevere to get where you want to go -- but once you get there you'll know you've accomplished something.
Reply to
Tim Wescott
OK Gang. You have provided very helpful advice. Thank you. So the symptoms are the same even when I start the motor with the throttle, off, and then turn it up slowly. The motor runs only as long as I hold the start/reset button down.
I think that Tim's comments are on the money.
The battery pack voltage right now is 7 volts. With full thottle (without the prop), the voltage across the motor terminals is only 2 volts. When I charge the battery, the battery voltage is 8.5 volts, and with full throttle the voltage across the motor terminals is only 2.5 volts. (You're right about the manual dexterity comment....these maneuvers took several tries.)
Motor shaft doesn't seem bent. And the propellor spins normally, and the resistance of the shaft seems "normal." I did manually spin it a bit to get the feel of it before we had the crash. I'm not sure, but I don't think this motor has a gear box.
So, I will first order a battery pack. The replacement part listed in the manual is HCAM3467. I can find this at Tower Hobbies on line for $17.00 + $4.00 shipping. I think I'll start with this plus another motor (HCAG3475) which is only $9.00. The Electronic Speed controller (HCAM3471)is $31.00, so I'll hold off on this for now.
I'll post you once I receive these and give it a try.
So I've spent the last 5 hours on this project....hmmm...
Ken and Brian
Reply to
kkt_mag
Before you go out and buy s new battery pack- it sounds to me that the speed controller may be what is fried- I say this because high drains usually do not fry NiCad or Nimh batteries- in fact this is the best thing about these bateries- they are capable of producing high current with no damage. You should check the voltage BOTH at the battery (with full throttle) and at the motor. If the battery voltage with the system is: system on full throttle----------- system off at battery at motor indicates 8 volts 7.8 v 2.5 v fried controller but, for example- 8 v 4 v 2.5 v means fried battery
Batteries are generally pretty tough, and other possibilities such as wiring and connector problems are also possible. A prolonged high current to the motor would heat it up, could weaken the magnets, and could damage the control speed. Paul
kkt snipped-for-privacy@yahoo.com wrote:
Reply to
Paul Ryan
Okay gang: Again, thanks to all. Someone was kind enough and very thoughtful: he sent to me spare parts from an old Park Pilot gratis. By changing out the parts one by one, it is now clear that we fried the controller and the motor, but the battery pack is fine.
We were up flying this past weekend, and had a wonderful time.
Thank you to everyone for your help!
Ken and Brian
Paul Ryan wrote:
Reply to
kkt_mag
Now this is what Ezone is all about. What a Uplifting thread :D I know this thread is Almost a year old but I hope you and your son keep involved with RC Flying.
Regards Malcom
Reply to
kushal_22
| Now this is what Ezone is all about. What a Uplifting thread :D
... except that this is not Ezone :)
(You may reading this on Ezone, but this is Usenet -- not Ezone.)
Reply to
Doug McLaren

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