Great info guys, thanks! I pulled out the ruler, and holy cow that's way back from the manual's recommendations. The rest of that lead is coming out.

You guys probably saved me two weeks of playing with the CG to get there. I've only averaged 1.5 flights a weekend with all the gear problems. Hopefully I can start getting smoother landings now.

Sorry I said 155mm mine actually 150mm

Wow, talk about being a clown. You guys just helped me realize I had my CG marks measured from the wrong location... They were measured from the molded wing roots...

My CG is way off! Like 25mm too forward!

Either way, you've saved me a ton of time. Thanks again.

4kg Ya right. If they did 4kg, then no one would be having any concerns with their gear on the stock 2.9-3.1kg bird. These have been around for years even with the metal trunnions and they have limits. You can push it a little further like FW has but there are plenty threads documenting their use with even lighter stuff with fair pilots.

PZ-15090
Servoless Retractable Landing Gear
After 10 seconds Auto power-off Protection system
Double Shock Absorption Design
Completely protect the gears
Dimension：65.8*35.1*25.1mm 2.59*1.38*1.0inch
Maximum travel: 90°
Torque: 2.5kg-cm
Speed: 0.7s/60°@4.8V 0.55s/60°@6V
Operating Voltage: 4.8v-6v
Weight: 32g

Used for airplanes wing span around 1.5m
Support Flight Weight 3kg
Φ3mm

Originally Posted by PeterVRC

I have five large aircraft using those "Medium" sized retracts. All over 3.0Kg.
They don't really quote specs, but it is something in the area of "Suitable for 2.5Kg" (or 2.7Kg) aircraft.
Like most things, specs are rubbish... only useful as a guide...
So I assess....test... see what happens....
I have not had one failure of any retract, though every one I have is metal trunion converted. They tear out of a plane long before they get any chance to fail!

So I am not worried over them one iota.... they will even do 4Kg fine.

Originally Posted by Whiskey Whiskey

Wow, talk about being a clown. You guys just helped me realize I had my CG marks measured from the wrong location... They were measured from the molded wing roots...
My CG is way off! Like 25mm too forward! Either way, you've saved me a ton of time. Thanks again.

Well all my planes land on grass, and I have not had one retract failure of any of the sizes. (small, med, large). Close to 30 mediums in use across all those planes that use them - every one is metal trunion. None use FW or Dynam etc retracts, all get replaced with whatever the HobbyKing and PW-RC versions are... they are identical.

I use Small up to 1.7kg

A crossover of Medium from 1.4kg to, more commonly 2.7Kg area, but seeing they keep on working I don't change out even to 3.6Kg now. The Me262 has now done TONS of flights, well over 50 (prob towards 80, and the most of all my large planes) without any issue on its Mediums (or any aspect of the plane whatsoever - it is the best value and result foam plane I have seen!).

Large on 2.5kg upwards, IF it seems required.... and that generally means a tail dragger (eg 1600mm P-51 etc). Trike aircraft cope easily on the Mediums, seeing there are three.

So where did it ever say "2.7Kg total aircraft weight" that could possibly mean anything of use? Two used? Three used? Four used?
And I have high stress proof (grass/rough landing areas) over long term to show they cope fine (in a trike) out to at least 3.6Kg, so I don't care what their "plucked out of the air' specs say.
I never pay much attention to ANY specs, except as an initial guide. I can real-world assess things very well just by looking at stuff and how it is made, open them up etc. I have never really broken anything (motor, esc, retract..... any item used) in aircraft use. Though I have broken PLANES by crashing them... hitting trees.... too low a pass clipping a wing.... hitting fences.... tearing out a retract, or two, on grass takeoff attempts (but no retract broken). And fried a motor or two by pushing limits on a test bench - but that is an allowed for outcome in such cases (and better there than in flight!).

wow, I've got to be about an inch further back then that? Mine's at the back edge of the big red square; looks around 180mm? Oops!

Originally Posted by Odysis

wow, I've got to be about an inch further back then that? Mine's at the back edge of the big red square; looks around 180mm? Oops!

Has yours been flown at that CG?

Yup, lots. Felt fine... I use about 15deg of stab deflection, and it's plenty stable, even with the gear down. (balanced with gear down, as it's the most critical)

Hmm. I bet she slows down nicely for you on landing at that CG (depends a bit on your AUW which I'm guessing isn't overly porky).

I just posted the old pictures from earlier discussions for WWs benefit. Many ask for some physical marker to work from and we found the ailerons wire pass through box to be a good reference.

I flew CG165. Odysis I think you set a new record for aft CG. That's actually past stable neutral. Mind you the stickers vary as they are... stuck on. But curious on the details of your flights. Did you post Video?

Originally Posted by Maxthrottle

I just posted the old pictures from earlier discussions for WWs benefit. Many ask for some physical marker to work from and we found the ailerons wire pass through box to be a good reference.

I flew CG165. Odysis I think you set a new record for aft CG. That's actually past stable neutral. Mind you the stickers vary as they are... stuck on. But curious on the details of your flights. Did you post Video?

Hey Peter do you have a YouTube channel? Was hoping to see a few of your Su35 vids

No, no vid. My camera (phone) is cactus, sorry.

It flys fine, on the border but still just on the good side of neutrally stable. At high AoA, it does turn unstable, but that's 30+ degrees or so.

It's all stock, so I'm not sure how I've ended up so much further aft than anyone else? 740g battery smack in the middle of the tray.

*OK, just re-checked it. The stickers line up with roughly the middle of the aileron holes, so around 165mm. Not as bad as first thought!

Originally Posted by PeterVRC

Well all my planes land on grass, and I have not had one retract failure of any of the sizes. (small, med, large). Close to 30 mediums in use across all those planes that use them - every one is metal trunion. None use FW or Dynam etc retracts, all get replaced with whatever the HobbyKing and PW-RC versions are... they are identical.

I use Small up to 1.7kg

A crossover of Medium from 1.4kg to, more commonly 2.7Kg area, but seeing they keep on working I don't change out even to 3.6Kg now. The Me262 has now done TONS of flights, well over 50 (prob towards 80, and the most of all my large planes) without any issue on its Mediums (or any aspect of the plane whatsoever - it is the best value and result foam plane I have seen!).

Large on 2.5kg upwards, IF it seems required.... and that generally means a tail dragger (eg 1600mm P-51 etc). Trike aircraft cope easily on the Mediums, seeing there are three.

So where did it ever say "2.7Kg total aircraft weight" that could possibly mean anything of use? Two used? Three used? Four used?
And I have high stress proof (grass/rough landing areas) over long term to show they cope fine (in a trike) out to at least 3.6Kg, so I don't care what their "plucked out of the air' specs say.
I never pay much attention to ANY specs, except as an initial guide. I can real-world assess things very well just by looking at stuff and how it is made, open them up etc. I have never really broken anything (motor, esc, retract..... any item used) in aircraft use. Though I have broken PLANES by crashing them... hitting trees.... too low a pass clipping a wing.... hitting fences.... tearing out a retract, or two, on grass takeoff attempts (but no retract broken). And fried a motor or two by pushing limits on a test bench - but that is an allowed for outcome in such cases (and better there than in flight!).

Hey Peter do you have a YouTube channel? Was hoping to see a few of your Su35 vids

Originally Posted by Maxthrottle

I just posted the old pictures from earlier discussions for WWs benefit. Many ask for some physical marker to work from and we found the ailerons wire pass through box to be a good reference.

I flew CG165. Odysis I think you set a new record for aft CG. That's actually past stable neutral. Mind you the stickers vary as they are... stuck on. But curious on the details of your flights. Did you post Video?

Hey MaxThrottle do you have a YouTube channel? Was hoping to see a few of your Su35 vids (sorry got mixed up)