Official Freewing Twin 70mm SR-71 Blackbird with Gyro EDF Jet Thread

[EDF-Jetpilot]

Would you "always" paint a tailpipe black inside, as you wrote in post #82? Even something like an F-35 where the inside has a white ceramic coating?

:handshake:

[EDF-Jetpilot]

https://www.hobbysquawk.com/forum/rc-airplanes/rc-jets/419430-official-freewing-twin-70mm-sr-71-blackbird-with-gyro-edf-jet-thread?p=420072#post420072

"Always" is not the same as ""sometimes"

"Very few" is not the same as "none".

Incidentally, the last several FW models I have bought did not have unfinished white EPO inside the tailpipe. They were painted grey.

Which ones were they? ...I can't remember.

[EDF-Jetpilot]

Even that statement is disputable, since some designs (but not all) actually do a good job of fairing in the blunt rear end of the motor.

There will hardly be any more thrust, firstly because of the higher weight, secondly because of the additional power branch (it all comes from the drive battery) and thirdly because of the even greater thrust disturbance caused by the additional material in the thrust tube, unless in very exclusive cases it is perhaps an absolutely aerodynamic mounting cone... but even then points one and two are still in the negative range.

[EDF-Jetpilot]

Just waiting for someone to try and fly this thing off of grass before i pull the trigger.

I wouldn't hope for that, because in my opinion it's clearly not a grass runway aircraft... that wouldn't be appropriate for the species and it's certainly not fun to fly on grass on a regular basis. You'd be better off looking for something that can fly on grass, like an A-10, MIG-29, MIG-25/31 or something like that, that will definitely make you happier. sorry for my direct answer to you. You can also hang this beautiful thing from the ceiling, this machine looks very good there too. Of course, only if you buy it and then don't want to fly it on grass.

[EDF-Jetpilot]

Would you "always" paint a tailpipe black inside, as you wrote in post #82? Even something like an F-35 where the inside has a white ceramic coating?

you're crazy about the bright jet tubes... I already had an F-35 from Freewing, but with a new one I would probably paint the inside cream white, because the F-35 isn't actually black originally, you're right about that.

Ich mache das hobbymäßig und bin daher mit meinem „immer“ oft flexibel. Aber Du bist wie wir Schweizer… ziemlich genau und ausdauernd.

:lying_face:

[ElCid]

Just waiting for someone to try and fly this thing off of grass before i pull the trigger.

[kallend]

Thanks, I like that much better than bright and if you don't use the flash of the camera to illuminate the inside of the real jets, it looks black, except for the rearmost slats of the nozzle outlets with the coatings... but the inside of a "cave" has always been black. ;-)

Would you "always" paint a tailpipe black inside, as you wrote in post #82? Even something like an F-35 where the inside has a white ceramic coating?

[EDF-Jetpilot]

I haven't tried the reverse thrust yet, I was going to use the extra channel for separate nose steering but waiting to get more flights on mine before I do anything else. The chute works way better than I expected but it is a pain to pack if you have big hands and fingers like I do, I use my pinky finger to hold the chute in while closing the hatch and it still wants to pop out. It is a cool factor for sure but very effective. I have tried reverse thrust on other jets and it makes a mess inside the fuselage, I fly off pavement and it gets to dusty and sucks all that into the fan, besides I have plenty of runway so I don't need reverse anyway so the chute works for me. I now have 6 flights on mine and its a very nice flyer so far.

You have a nice Avatar! I have this Plane HSD-F16 105mm S-EDF whit Belgian Finish comming soon for my this April. I will also buy the SR-71 as soon as it is available in Europe (Switzerland)... it will be an expensive hobby year.

[EDF-Jetpilot]

This is my version of the M-21.

Nicely done with your black linkages!

[EDF-Jetpilot]

OK, in the spirit of helping, here is a picture of the tailpipe of the SR-71 at the SAC museum in Nebraska, that you can use as a reference for color matching. The nozzle was made of Hastelloy X (a nickel alloy), which suffers minor surface discoloration due to the high temperature of the jet exhaust.

This SR-71 looks grey even on the outside in this picture... I think the exposure is not very good and much too bright. Because even with real jets without bright interior lighting and incorrect image exposure, the inside looks black, except for the rearmost slats of the nozzle outlets with the coatings... but inside a "cave" has always been black. ;-)

I don't really care... I like black and I'll keep doing it like that. But with the SR-71 from Freewing I'm pretty sure I'll install an afterburner, then I can even imagine aluminum foil in the innermost part, but not all the way to the back, it has to be black there for me, that's perfect for me.

[EDF-Jetpilot]

I'm a major "scale" guy and I think your black thrust tubes look great. Light absorption could be an issue if you did choose to add afterburners but I think the black thrust tubes look better than the white stock ones personally.

Thanks, I like that much better than bright and if you don't use the flash of the camera to illuminate the inside of the real jets, it looks black, except for the rearmost slats of the nozzle outlets with the coatings... but the inside of a "cave" has always been black. ;-)

[Aros]

This is my version of the M-21.

[DCORSAIR]

I haven't tried the reverse thrust yet, I was going to use the extra channel for separate nose steering but waiting to get more flights on mine before I do anything else. The chute works way better than I expected but it is a pain to pack if you have big hands and fingers like I do, I use my pinky finger to hold the chute in while closing the hatch and it still wants to pop out. It is a cool factor for sure but very effective. I have tried reverse thrust on other jets and it makes a mess inside the fuselage, I fly off pavement and it gets to dusty and sucks all that into the fan, besides I have plenty of runway so I don't need reverse anyway so the chute works for me. I now have 6 flights on mine and its a very nice flyer so far.

[kallend]

Out of curiosity, if anyone has tried both the chute and reverse thrust (not at the same time) which was more effective in stopping the plane?

Clearly the chute wins on coolness.

[GliderGuy]

Great! Good info DCorsair

I will…but I will probably use the chute only on occasion. Repacking it every flight might get tiresome. Maybe not. Gotta buy a totally new radio set-up first.

Please post a flight report.

-GG

[DCORSAIR]

All done except for the decals.

Post build impressions…drum roll please…and I am not affiliated with MRC LOL…here goes…

The quality of this PNP plane is excellent. I did not run into any snags getting her ready. The Admiral 6000 needed to be slid to the aft of the front battery bay to get the CG spot on (gear down). If one were to go with 2 batteries, some tail weight would be needed.

The range check was great. All quadrants. I have yet to taxi her, so I cannot comment on how well the nose gear is centered straight.

I added RF Chokes right at both ESCs on the lines that head back into the fuselage and an additional RF Choke between the UBEC and the RX. There is a green toroid ferrite choke already installed. I added another. RF Chokes are SOOO important to help prevent RF noise from the ESCs from disrupting your receiver.

A majority of the screws are Torx. I liked that! The inner main doors came default to “not scale”. They close after gear extension. I liked that that, too. It gets them out of harms way.

All the factory-installed screws were tight! The gyro was default “normal” (steady green light), and test “flying” in my hands proved that the gyro configuration is correct. There is an App you can download to configure the gyro, should you need to.

With the magnetic nose off, there is ample room in the bed of my Titan. Her right main fit into the tie down for the B-2…nice.

There is a seam line in the tail cone. I lined up the inner control surface with this seam. Then I lined the outer control’s trailing edge to the inner control’s trailing edge. I’m gonna start with about 3-5 mm of “trailing edge up”. Most of my birds require up elevator in cruise.

Rain for the next several days. Ugh.

Overall, I am VERY well pleased with the quality and design features. I’m ready to see how she holds up to her first 1,000 landings.

Next up…pilot flight reports as soon as the weather permits. Not going with any EXPO and will maiden on low rate. 6 ch gear, so no chute, no gyro settings changes, and no reverse thrust. I do plan to upgrade radios, so these other “neat’ features will be enabled soon. Timer is set for 3 minutes, and I will maiden at 50% throttle cruise. I anticipate 4-5 minutes at 50% throttle plus some full power acro (loops) and fast low passes…leaving 3.8V is my goal.

-GG

You have got to try the chute, it works great.

[kallend]

I think I speak for more than myself when I say a less abrasive bedside manner would be warranted and is always appreciated in this forum community.

OK, in the spirit of helping, here is a picture of the tailpipe of the SR-71 at the SAC museum in Nebraska, that you can use as a reference for color matching. The nozzle was made of Hastelloy X (a nickel alloy), which suffers minor surface discoloration due to the high temperature of the jet exhaust.

[Aros]

Your model, your choice, but don't pretend it's scale.

I think I speak for more than myself when I say a less abrasive bedside manner would be warranted and is always appreciated in this forum community.

[kallend]

We can "Always" count on a "discussion".

I'm retired, it's 13 degrees F outside, all my chores are done, all my model winter maintenance is done. I don't watch TV. My "hangar" is full to overflowing. . .

What would you like to discuss?

[Evan D]

We can "Always" count on a "discussion".