Prekin

My Feedback: (19)

Hi Laurent, I´ll check it.

Prekin

My Feedback: (19)

Hi Laurent,
thank you for the link. It´s very useful, because I wasn´t sure about the mouth of the cannons. As you can see, I found some pictures. The barrel is over the fuselage and some pictures, where it is in the engine cowl.

Laurent45

hi Prekin how willl u make to enlarge all the nose???? or will u keep the la 7 nose form?

Laurent45

don't forget to look picture of the la 7 in Praha air museum! u can find good pictures as the la 7 of monino museum

Prekin

My Feedback: (19)

I have original cowl from ESM La-7. La-7 and La-5F , FN had the same cowl, but they had different oil cooler, comressor air intake, retract. But maybe there were other and bigger differences. My La-5Fn will be only semi-scale.

I tried to upload some new pictures, but there is some problem. I don´t know if it is on the my side or on the RC Universe´s side.

Prekin

My Feedback: (19)

Finally I can upload some more pictures. I was in the air musem Praha- Kbely last september. It was beutiful, but the hangar where was the La-7 was very dark, and I wasn´t be able to come to the airplane closer. So my photos are not very detailed. []

Laurent the last picture is for you, you can use it as a label (sticker) for your car.

rcfan450

My LA is finally done. I'm just waiting for good weather and no snow on the runway to fly now.

Skip to the last 10 seconds of this video for a quick glance.

[youtube]http://www.youtube.com/watch?v=VAJUiySCUjA[/youtube]

Prekin

My Feedback: (19)

Hi rcfan,
I see, that you enjoy the winter and snow. Is it 4WD or 2WD?
In the winter put the skis on my airplane and walk the dog.
http://www.youtube.com/watch?v=_KyNBVal64Y

Could you upload some pictures of your La-7, please?

Laurent45

Hi!!! Tank s for thé pictures !! I have been in Prague in june i didn t know at this moment there was this museum

rcfan450

A few notes:

- my plane weighs 18.2 or 18.8 pounds or anywhere in between depending on how my bathroom scale feels
- built a nice carrying thing out of pvc to transport it safely, will put foam on the wing tips since they're about 1/2" away from both ends of the truck bed
- used carbon fiber rods for exhaust and guns (don't care if it isn't totally scale, looks cool)
- not completely happy with the color of exhaust paint, I may paint it again with something darker. It's almost purple looking
- glued and screwed the wheel covers, hopefully they'll stay on
- robart retractable tail wheel works good, was a pain to figure out
- prop clearance is about an 1/8", perfect!
- the XYZ 53 fits perfectly with a little clearance.
- no choke wire, dremeled some pieces of the carb off to make things work
- had to shave some wing flap well edges so the flaps would go in

- the motor starts and runs great
- CG is ...I can't remember now.
- put a smoke system in it too
- built a balsa cover so aileron/flap servo wires wouldn't interfere with rudder/elevator wire. Plus I wanted them to be securely velcroed down so as to not interefere with the radio in any way.

I think that's about it.

Yes, the truck above is 4x4.

rcfan450

more pics

Prekin

My Feedback: (19)

The engine looks very good. I´m looking forward to see a video with the maximum speed of your La-7.
Don´t worry about the color of the exhaust paint, I think, that it is the last thing, which could has bad impact on the flying properties!
What spinner do you have? It looks very scale!

My CG is 10mm before the original (manual) CG. I had ESM Stuka. After the first flight I had to change it, because in the manual it was a little bit in the back.
Now I´ve passed the first season with the La-7 and now want to change it in the La-5FN and also I want to have retractable tail wheel. I´m waiting for the small rail. I want to have a opening canopy and I need two rails for the leading grooves.

rcfan450

That spinner is the one built specifically for this plane from Troy Built Models. It's on back order quite a bit. I'm not sure how I lucked out and got one before it went on back order. (It actually has major balance issues and I'm waiting for a replacement...)

I hate adding weight to planes so I'm really hoping that 162mm is fine. With smoke oil, along with gas, we'll see I guess. Seems like stock was 165 and everyone thinks that's too tail heavy. I installed everything as far forward as I could (except the motor, I could push it out with spacers...but I'm not going to).

Putting rails on for a sliding cockpit would have been sweet. It seems kinda lame to do all that work on the cockpit, then just seal it off with the canopy. But I wanted to keep things as light as I could. Post pics if you do so.

Maybe New Years Day I'll maiden it. We'll see what the weather has in store for me. I'll video it.

AZThud

Sure looks nice, I hope your maiden goes well, I have the CGof mine in the 155mm range and it flies very well and tracks like an arrow, my experience for what its worth is that ESM publishes the CGa tad on the tail heavy side, so I suspect yours will be more sensitive to pitch than mine so please be careful and again good luck.

Cheers

Prekin

My Feedback: (19)

I think, that everyone hates adding weight to planes. But I agree with AZThud. I have CG in the 155mm, and it flies very well. I rather add 100g than I destroy the aircraft. But it is up to you. If you fly with the acrobatic specials, it won´t be a problem for you. So good luck with your maiden flight.

rcfan450

What is the final AUW of your planes? Mine is 18.5ish dry, it'll be over 20lbs full.

AZThud

Mine is eletric and just over 20 pounds

Cheers

Prekin

My Feedback: (19)

Mine with the ROTO 35 is 7700g (16,9 pounds), but after the remake it will be heavier.

rcfan450

Is that dry Prekin? Retracts? That is pretty light!

I attempted to maiden today. Didn't get very far. The second the tail lifted it took a hard left and went over a snow bank. Didn't quite clear the snow bank. Ripped the sierra gear off (just one of them, busted it at the nub). I spent the afternoon and fixed it. Pisses me off though. I got video of it but I've been too pissed to even look at it, I vented my frustration fabricating a strut fix instead. It broke the nub on the end of the strut off that you insert and tighten into the main actuator. I used a caliper and ground me another perfect piece from a bolt shaft, drilled it into the strut, works like new.

Crash theory. My only guess is that I didn't have enough (or any) toe-in alignment on the main wheels. I've flown planes with the tendency to pull left on take off before but that was like the left wheel was locked! (again, only after the tail lifted did it go wacko) It was bad.

Dumb question/observation. So this is my first time using the Great Planes CG tool. Do you hold the plane perfectly level, then let go and see which way it goes? Cause if I hold the plane even a hair either way from level, we're talking a half inch or less, it'll tip that way regardless whether that's the way it is truelly balanced or not. Maybe I'm not doing it right I don't know... Maybe I'm right at 155mm which is where I was testing it and it's so close to that that it doesn't matter. For sure I think I'm under 160mm though, better than I thought previously.

Anyways, it's ready to go again. 0/1 succesful flights thus far. :-(

Prekin

My Feedback: (19)

I´m sorry about your maiden flight, I believe, the next time it will be successful.

The weight 7700g is dry, with the fuel it is about 8200g (18pounds), with retracts.
When I balanced my La-7 I held plane upside down perefectly level. As I wrote, CG is 155mm. Every plane which has CG up to wing I hold upside down, because if you want to find CG, you must have it under the wing. In this case you can find it, because it is stable configuration. It is from Physics. I do it with every airplane and I´ve hadn´t any problem yet.

sgrady

My Feedback: (5)

Any nice fuel fill ideas ?

Prekin

My Feedback: (19)

In my Bf-109G I had it in the cockpit, and in my CMP Zero I have special service door, where I have a fuel fill, switches and retracts fill. I had a ESM Stuka where I had fuel tube, which was hidden in the cowl.

Prekin

My Feedback: (19)

Here is the service entry on my CMP Zero in the progress. On Friday I will send the picture where it is done.

rcfan450

Crashed twice now. The second time was worse.

This was the first flight. Skip to 4:33 for two seconds of ugly LA-7 Video.

Any suggestions are welcome.

[link]https://www.youtube.com/watch?v=4E61jQ8ryz8[/link]

I forgot to add. After this ugly maiden attempt, I borrowed the CG tool and did that again with the plane upside down. It was 160mm dry. Put a few ounces in and got it to 156mm dry. On top of just adding gas, I also have 16oz of smoke oil in there too so it is plenty nose heavy for take off.

The 2nd flight was much worse. I wanted to make sure I had plenty of speed before taking off, so I had speed - maybe 1/3-1/2 throttle - and it kinda came up itself but it did it before the tail even came up on its own. Still, typical loop over left wing take-off. Much more damage this time.

Do I need to force the nose down to make sure the tail comes up, then get lots of speed, then let it take off? This plane is kicking my butt. I've owned a few warbirds before (P51's), they were nothing like this one.

Kinda makes me wonder if the elevator stabs are/have too much "up" in them. Being 1/3-1/2 throttle and the tail is still on the ground....hmm....

djmoose

My Feedback: (4)

fan450, I hate to say it, but it LOOKS like you didn't give it any right rudder to keep it straight.

It looks like typical spiral slipstream and you didn't correct for it.

Now, I say it LOOKS like that...we're you in fact giving it right rudder?

I ask because right before it hits the snow, the plane stops turning and goes straight for a second.

Let us know. It APPEARS that your giving it full throttle and that blast is kicking the rudder out.

Like I said, that's what it looks like, explain in detail how you're taking off.