Dr Hu

Bought a PZ spitfire after months of drooling in the Model Shop - I'm used to flying gliders & slopers mainly - so this is a return to a hobby from when I was a teenager/young man!

The maiden flight - stock battery, low rates etc - was bad - very bad.......

I launched at WOT it went up to about 10-15ft at most, then came nose down pretty rapidly - smashed the prop off, cowling, destroyed firewall, seized motor - cut motor wire in half etc, plus some damage to wing leading edges etc.....
It flew for about 5 -6 sec max........

After a lengthy rebuild with Araldite (epxoy resin glue), a soldering iron, taking the motor apart to reshape the motor casing to get the bearings lining up again & reset the pinion gear which had slid about 1/4" down the shaft - its back together....I reckon most of the damage was done by the heavy battery slamming into the motor/gearbox from one end, the ground from the other! I think the firewall/battery moulding is very flimsy translucent plastic, it could have been made much stronger easily.

I haven't flown it since, waiting for perfect conditions before trying again - I did a CG check after reading on here that it is worth checking......mine was MILES out - way too nose heavy - it balanced approx 50mm!! wish I had read on here before maidening........

So I have amended the battery mount slightly to move the battery back a bit (that helped a fair bit) and added a strip of lead on the rudder. It now balances bang on at 67mm - hopefully it should take to the skies a bit better now.

What do you guys think went so wrong - I barely had chance to get my fingers on the stick!

Should a RTF that is advertised as a grab & go need this sort of checking?
Its a good job I have previous aeromodelling experience and know the heartache that goes with the joy!

max2112

Sorry to hear about your maiden woes, Dr. H.

I feel your pain. I had a Wattage P-51 do pretty much the same thing. One thing I've read about, here and on RCU, is to launch the plane a good 10 to 12 degrees above the horizon. When I throw my PZ FW-190 it always tries to bank hard to the right also.

Good luck on the re-launch!

John

p_r_i_m_e

after reading many of this type of thread on many different forums (and having experienced the same as you except with an art tech cessna) it seems that almost all RTF's are really far from ready to fly.

duckalliance

It's odd that your COG was way out, picked up a PZ spit this weekend and (apologies for rubbing it in) she flies great - replaced the nimh with a lipo which has improved things a little too!

It's always crap when you break your model, but there's a lot of model shops who sell all the spares online for the parkzone kits, you can buy a full replacement fuselage (amongst lots of other things) so i guess that's a comfort factor where your wallet can take it!

alas i bent the shaft on a motor last weekend because i swapped the stock motor and didnt check the c of g on a model - flew for around 5 seconds and nosed heavily into the ground...

DetroitHawk

Low rate might not of given you enough throw to pull out of it.

Balil

i never fly my pz spit on low rates.. there just isnt enough throw in the inner most holes for my liking... so for me its either high rates or nothing

fezz

+1

Glacier Girl

Well something else to consider. It's possible you stalled it. And being nose heavy would have made it even worse. Most warbirds tend to have too fly fast due to wing make up, and if you had her climbing too soon, before the speed had built a stall is a real possibility. The PZ Stang was famous for this, a lot of them met their demise due to a poor launch.

One other thing, for the price of a stock motor/ gearbox, I wouldn't try repairing the one that got crunched. It's just another thing that could go wrong on the next launch, a little binding and it doesn't spin up fast enough and you're going to see another stall or pancake landing.
Ask me how I know. LOL

fezz

flying habits - you learn that it doesn't take much stick movement to control the plane.

Dr Hu

OK - the 2nd maiden didnt go too well either.....

I got it all back together & balanced - couldn't wait to try again and tried when it was too windy really (hindsight eh!).....it went up like a rocket this time (different to the first) against the wind, and I was struggling to hold the nose down, it was veering off to the right so I fed in full trim on the ailerons, then I'm pretty sure it stalled (still going into wind - it was too far in front to really see what happened) at about 60ft+, then it just came nose straight down & planted big time.

Result was very messy - broken fuselage & snapped wings........

Now waiting for replacement airframe parts to come into stock in UK so I can repair - the only good thing is the parts are cheap for these Parkzone kits - so will cost about £50 to repair - rather than £130 for a whole new model.

crxmanpat

Dr Hu,

Sorry to hear of your troubles. I bought one of these last Friday, and had it airborne in under 2 hours (owing mostly to waiting for the NiMH to charge). It was not as fast as I had hoped (switching to Lipo power this weekend), but it did fly well. Got 4 flights total on it, even 2 in high winds (20kph+).

I have lots of experience with the ParkZone P-51, so that may have contributed to my success in flying the Spit.

Good luck on your rebuild and subsequent remaiden.

glider64

Hello everyone i have just joined this forum and would like to say hi; i`ve also just bought a pz spitfire and agree that the low rates are just asking for trouble, it took me four flights the day i flew it to break it can`t blame the model this time i tried a fast turn to be followed by a low pass only i went in on the turn and considering it was flat out i got away lightly not too much damage and could even fly soon with some epoxy and tape but i`m waiting for the new cowl and fire wall and spinner i also think there is a need for a bit more power

DetroitHawk

Seems like the stock setup is always underpowered on these planes. Lowrates work for nice and easy flying but if you didn't just start flying yesterday i would never use them. I rather have enough control then too little.

I don't think that having this plane nose heavy is a bad thing. Mine flys alot better not that i have it nose heavy. I had the CG set perfect and it just seemed like the plane flew like crap, however soon as i set the CG forward it really is a nice plane to fly.

K CLOSE

I'm with Detroithawk on this one. I know others have reported diffrent, but all my PZ stuff seems happiest on the nose heavy side. I again reiterate that no one should madien one of these HAND LAUNCHING THEIR OWN PLANE. Teach a friend how to toss if 'ya gotta, but have your hands on the wheel as it were. No two PZ's fly exactly the same in my opinion, so heads up. All the reading in the world won't buy you crucial seconds getting your hands back on the sticks.
Just sayin'

fezz

I've launched 2 different planes - they may dip slightly on the initial release but climb right out - WOT

I can see where the stock battery could slide forward a bit too far (unlike the LIPO which fits snug in the frame) if it isn't snug down enough.

You could block the stock battery to the rear of the tray with a piece of foam to get the CG where it needs to be - it will also keep the battery from moving in flight.

crxmanpat

Fortunately for me I'm left handed, so the TX config works out for me. I can give a good toss with my left hand, while the right is already on the sticks ready for any course corrections needed.

I also give my planes a hard toss. I once tossed my P-51 so hard the nose cone split in two and came off at launch. Of course, it was already damaged on the previous landing which was on asphalt. :p

DetroitHawk

http://media.putfile.com/PKZ-brushless-spitfire

this is my maiden that i hand launched myself. I throw it up a little and give it a firm throw. I do however practice my throw with a followthru that lands my right hand back on the stick ASAP.

DetroitHawk

i think this video came out with a higher quality

http://media.putfile.com/spitfire-maiden