#905 P51 Mustang

[pedwards2932]

Well mixed results. Flies pretty good but I hit a power line and nose dived in on the last flight. Will need major surgery to fix. I didn't like the way the nose was done so I think I will beef it up where the prop bushing goes. I may build another one from scratch to see if I can improve it some. I had about 800 turns on here is the video:
https://www.youtube.com/watch?v=YqJ0G9MJo68

[pedwards2932]

The rebuild begins. I am making 2 of the front formers with the grain running in a different direction on each. I may use 3/32 since the plane needed nose weight. Also I increased the hole for the nose button to 10 mm. I plan on doing something different with the prop hub because it didn't seem to be centered properly.

[Blacksheep214]

Ouch! Sad day to see that happen! And on the maiden no less! Oh, well accidents happen. Glad she is still salvageable. The nose section was also a chief complaint of mine on the 900 series Mustang. There is little to no support, and if the worse should happen, the damage is pretty tough. I cross braced mine in the front, with extra stringers and I used sheeting to back the "firewall" where the thrust bearing makes contact with the front. I left only a big enough hole for the shaft and motor to fit.

[pedwards2932]

Since mine needed nose weight anyway I made 3 of front formers and have the grains running in different directions so it is like balsa plywood. I traced these from the plan and used my laser to cut out. I may do the whole model then I can pick the wood I want to use. Haven't decided if it is worth doing.....I'm thinking I would rather do the larger P51.

[Blacksheep214]

Pedwards,

In my opinion, the 400 series Mustang is much easier to get to fly and better built. I'm not saying abandon the 900 series Stang, just saying that for the long haul and ease of getting to fly, the bigger one is far better. Kind of surprising really, because I would figure as light as the 900 series bird is, it would be better. I guess it's just size that makes it harder. However, you had it flying pretty good though!

[pedwards2932]

I'm thinking of just ordering the plans for the 900 and make my own balsa parts. Might just order the plastic parts that I would need. I have several versions of the P51 I'd like to do. There is an Earl Stahl version of the P51 that looks pretty good as well. I'm kind of a computer nerd so I like making plan tracings and cutting out parts with my laser. I have started to do all the parts for the 900 because I want to build another and change some of the design (like the front end) and I think I want to decrease the dihedral and change how the scoop under the wing is done.

[pedwards2932]

I have all the parts redrawn and laser cut. I got the original kit one back together and printed and angled shim (5 degree) and have it trimmed pretty decent. I am working on a vacuform now to make some parts. Anyway I flew the repaired plane today:
https://www.youtube.com/watch?v=l-NCB_6o97U

[Blacksheep214]

I have all the parts redrawn and laser cut. I got the original kit one back together and printed and angled shim (5 degree) and have it trimmed pretty decent. I am working on a vacuform now to make some parts. Anyway I flew the repaired plane today:
https://www.youtube.com/watch?v=l-NCB_6o97U

When you say printed, are you using a 3 D printer? I have always wanted to try to build a flying model using a printer to make the parts. I wonder if there are plans out there to make that possible? That would be really neat.

[pedwards2932]

Yes I have an ANET A8....I just printed the shim for the nose to give it some down thrust and right thrust. It kept the Mustang from stalling. There are folks that have printed entire planes not sure you could get it light enough for rubber power but there are fair number of RC planes. I use it to make parts mainly and it is great for making special tools for building planes.

[Bill Gaylord]

Pedwards,

In my opinion, the 400 series Mustang is much easier to get to fly and better built. I'm not saying abandon the 900 series Stang, just saying that for the long haul and ease of getting to fly, the bigger one is far better. Kind of surprising really, because I would figure as light as the 900 series bird is, it would be better. I guess it's just size that makes it harder. However, you had it flying pretty good though!

I doubt many people would share that opinion, unless someone gets a 400 series kit with better than average LC wood, and then replaces the often heavy 1/4" square stock and stringers with lighter wood.

[pedwards2932]

Since I have the plans for the 905 series and have them drawn out, I think I will go with it for now. I am making some modifications as I have been testing the original build. I am going to use a magnet to hold the nose button in.....when it spits out at the end of the flight the model dives in. The flight video is with about 600 winds and it was kind of windy. I was using 3/32 rubber 2 loops that stuck out about 2" from nose end. I think the flight time was about 23 seconds. I have put in 1/8" rubber and the climb is much better so I will see how well it does with the nose button held in place and closer to full winds ( guessing I can go to 1000 winds). I'd like to see if I can get a minute or so. The field I am using is pretty large but with the wind blowing I was running out of field.

[Blacksheep214]

Yes I have an ANET A8....I just printed the shim for the nose to give it some down thrust and right thrust. It kept the Mustang from stalling. There are folks that have printed entire planes not sure you could get it light enough for rubber power but there are fair number of RC planes. I use it to make parts mainly and it is great for making special tools for building planes.

I wish I had one. I have to resort to scrap balsa. Please post an updated video after the mod, and with the larger motor in it. You are very close to the 30 second mark.

[pedwards2932]

Well I tried the 1/8 rubber 2 loops that stuck out of fuse about 2 inches and it seemed to have to much of a power burst. Then I tried 2 loops that were about 6" out of fuse and this seemed to do better..... it still files pretty fast. The nose section is getting worn out and the plane itself is looking worn torn. I think I am going to build another and start over. Here is a short video....it spits the prop out at the end so it looks like it got "shot down"

https://www.youtube.com/watch?v=13ty0Yx2SY8

[kittyfritters]

Try making your loops about 1-1/2 times the hook to peg length. That's usually a good place to start. Longer motors, generally, have less of a torque burst. Make sure the motor is lubricated...I use Armour All classic myself although I have used automotive silicone spray to good effect and some guys still use dish soap and glycerine. Whatever angle you put on the nose block make sure it's in tight. Wobbly nose blocks and loose prop shaft bearings make trimming difficult and waste power. From the video, powered flight is very good, now you need to keep the nose block in and work on that glide trim!

[Blacksheep214]

The nose section is getting worn out and the plane itself is looking worn torn. I think I am going to build another and start over. Here is a short video....it spits the prop out at the end so it looks like it got "shot down"

https://www.youtube.com/watch?v=13ty0Yx2SY8

That is my biggest complaint about the 905 Mustangs. The nose section is pretty weak. I just gave up on mine and built the 400 series Mustang and have had much more fun, and no mishaps or problems out of it. I repaired the nose on my 905 twice, and I don't think I can do much more for it. So it continues to sit in the salvage heap. I cringed when I saw it nosedive in the end though. What amazes me is that it seemed trimmed out nicely under power, yet it dives so harshly when it runs out.