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Old 11-15-2019, 02:30 PM
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Pilot 33% Pitts assembly

So I spoke to Lyman at Pilot USA and it turned out they had a new batch of 73" Pitts coming in with the Charlie Hillard scale scheme So they reserved one for me, which just arrived at my door today

I'm going to do a quick assembly thread on this. Plan is to go DA70 with the 2in1, smoke, Futaba electronics and A123 onboard power.

Ive owned PAU and EF before, but this is my first Pilot. Im impressed so far - overall the quality looks quite good, and the hardware pack is EXTENSIVE. I'm a scale builder as well and the bag of cables, fittings and screws wouldn't be all that out of place in a Proctor kit... its a bipe there is a LOT of hardware!!!


First few observations:
  • This kits has the updates they sent out for the 40%ers: Cabane verticals and all the cable quick mounts are stainless.
  • I bet they use the same hardware for the 33, 40 and 45%ers.. The cable end fittings are a bit overkill for this size.
  • This is the first plane Ive ever built with pre-hinged surfaces. The hinging seems .. OK.. but I would rather they have used hinge points... the hinging is a bit stiff out of the box.
  • Pre-built tank is a nice touch but its a bit on the small size for a 70 ( my flying is more iMac style than 3D and I like 15min+reserve) I may use it for smoke and get a 24 ounce main fuel tank. Also going to switch out their fuel lines for viton on the clunk and real tygon everywhere else
  • Published specs look good, I measured 73.5" actual span on the bottom wing, about 71~72" cowl to rudder, 76" overall spinner to rudder.
  • I have to measure it to be sure but I think I will need to extend the canister tunnel for the 70
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Old 11-15-2019, 02:33 PM
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The scheme is very well done. I'll get Kirby's or Callie Graphics to make me up a set of Pitts logos and some scale IAC decals and this bird will look schweeeeet.


That pre installed photo instrument panel is just calling out for a nice scale pilot bust
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Old 11-15-2019, 02:33 PM
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Hardware.. hardware... and more hardware...
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Old 11-15-2019, 02:37 PM
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That's all for today, have to get back to work.



First up this weekend I'll open everything up, take measurements and weights and figure out what servos I need and the drop for the header so I can get electronics and engine ordered.
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Old 11-15-2019, 03:20 PM
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I like the color...if I were to order one..it would definitely this one... looking forward to the build✔️
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Old 11-16-2019, 11:59 AM
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Spent some time in the shop this morning with my helper taking measurements.

First off - cowl.
  • 165mm from the firewall to spinner back plate.
  • 57mm vertically from firewall center to the top of the canister tunnel
  • Canister tunnel is 115mm high, 155mm wide and 390mm deep from the firewall to tunnel rear

Going off the DA70 3 view it looks like 75~80mm is roughly the drop from the exhaust port face to the tunnel centerline. So we are going to have to go with either the 60 or 90 and offset.... The trick is the wing tube is in the rear lower part of the tunnel so we may have to use the short drop and cram the canister up at the top of the tunnel.. trick will be to see how the stinger clears the tube - it might work better with a front dump.


The MTW110 (70mm diax360mm long) is the recommended can for the 70, but there is also a 120k short can (80x295) . I may call DA and see if I can use this instead, it might fit better.

I am also going to need 15-20mm of standoff.


The kit comes with engine templates for the 50-55-60singles, and canister mounts that look sized for the singles. I wont be able to use them.
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Old 11-16-2019, 12:02 PM
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See what I mean about the tunnel here... But on the bright side, the cowl IS over 11in wide so will clear the plug caps no problem.
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Old 11-16-2019, 12:06 PM
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Next I measured the surfaces and servo mounts.


  • Lower wing half 11.5"x33.5" with a 3"x30.25" aileron
  • Upper wing half 11.75"x36.5" with 3"x28.25" aileron
  • Rudder is 14.75" by 4.5~8.25" chord
  • Elevator halves are 12.5" at the widest by 3.5~6" chord
  • I confirmed standard case WILL fit in the ailerons, they are side mounted and the pocket is about 7/8" deep at the rear.
Running this all though the servo torque spreadsheet shows that even using 3D throws at 60mph my worst servo load is the rudder at ~ 200oz-in.


I like Futaba BLS,.. a BLS171 should be more than enough on each aileron, probably elevator as well. Rudder can probably get away with a 175 as well but I may bump up to 175 on ele and 172 on rudder.
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Old 11-16-2019, 01:26 PM
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To help other builders - this is what a standard case servo looks like in the wing.
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Old 11-17-2019, 09:02 AM
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This morning I got everything weighed and make some educated guesses about onboard equipment. Unless I make some MAJOR efforts to save weight I dont see any way to get this thing in the air under 21lb dry.

The main issue is that Pilot does a lot of things heavier than they need to. The base airframe itself is quite light, but a few things could be better- i.e. the wheel pants and LG fairings could both be made of carbon and probably shave a half lb off. They also used M4 bolts EVERYWHERE... absolutely ridiculous when M3s would probably be sufficient in most places they are used. Again I suspect that they just use the same hardware for all 3 sizes and its way overkill on the 70cc.

Built under 20lb this plane would be insane, but to do that I think you would have to stick with a 60cc single, use stock mufflers (too loud for me), go with ultralight battery setup, leave off the smoke system, and leave off the LG fairings/wheel pants.

Pilot could modify this kit to get some decent savings by making the gear fairings from covered balsa rather than FG, make the wheel pats from carbon, and use M3 rather than M4 hardware in all but the highest stress locations.
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Old 11-17-2019, 09:06 AM
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About the hardware... I really dont like the supplied flying wire ends. They are too big and bulky (esp. the tail) and have a lot of slop. I am planning to replace it all out with DuBro/Sullivan cable ends. Should tighten things up and save about an ounce overall - along with looking a LOT better.

I may add BUSA turnbuckles or Secraft tensioners to make setting the tension easier.

I am also tempted to selectively swap out aluminum screws in some areas. The 4 that hold the stabs on, and possibly even the strut mount bolts could probably be substituted with low risk considering the flying wires are taking most of the live load. (The stabs on my 50cc Edge are held on with nothing but 4-40s)
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Old 11-17-2019, 10:05 AM
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Looking good got the 120cc in that Scheme. Here is my 61CC Anana resting for warmer weather. Will follow.
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Old 11-18-2019, 11:12 AM
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Quote:
Originally Posted by jharkin View Post
the wing tube is in the rear lower part of the tunnel so we may have to use the short drop and cram the canister up at the top of the tunnel.. trick will be to see how the stinger clears the tube - it might work better with a front dump.

Quote:
Originally Posted by jharkin View Post
The kit comes with engine templates for the 50-55-60singles, and canister mounts that look sized for the singles. I wont be able to use them.
Be sure to keep exhaust heat away from the wing tube both during and after flight. The tunnel will heat up on the ground after flying. Since you're going to have to make up new can mounts anyway, I'd suggest considering the KS Comfort Mount to allow for unrestricted airflow (among other benefits). I put them in my Laser - very happy with them. I have a laser temp gun if you ever want to borrow it.
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Old 11-21-2019, 12:16 PM
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Hmmm.. I think I may know who this "random guy" is. I still need some stick time on the AJ Laser

Ive got a temp gun (and an IR camera from doing home insulation work) but thanks for the offer. The KS comfort mounts dont come in a 70mm size it seems....


In other news: Vernie from DA helped me come up with a canister solution for the DA70. To get enough of a header drop I'll be using the 60mm with a couple of exhaust flanges (from the DIY header kit) as spacers. The overall length on the 110h will come to 570mm from the rear exhaust port, so this *should* fit with room to spare if I extend the tunnel to the former at the wing TE.

Stay tuned....
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Old 11-24-2019, 03:06 PM
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With lots of parts in the mail I started on some other projects. First up is decommissioning of my old faithful PAU Edge (and by old.... well the manual from that airplane still said “BME Aircraft”...... it’s old )

(taps playing)..


The airframe is getting parted out - Im selling it and the servos, keeping all the other electronics for the Pitts. Its got an older 50 (serial 4605) in it but the engine is still strong.... hmmmm.... maybe it needs one of those new EF 85inch Etras ?
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