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Kingtech JMB jets 3m PC-21?

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Kingtech JMB jets 3m PC-21?

Old 05-25-2018, 04:57 PM
  #26  
ltc
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Originally Posted by Neil Guildford View Post
I hadnít really thought about the heat issue as the turbine itself is further back in the nose. Iíll have a think and maybe just monitor it when I first run it up.
Please keep an eye for early signs of paint softening/blistering on the cowl halves.
Similar issues have been reported on the Skymaster PC-21
The most common fix is heat paint and/or heat blanket
Old 05-26-2018, 01:03 AM
  #27  
Dave Wilshere
 
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Neil

the joiner gets super hot, you will need to protect the fuselage top cover, it’s worse when you stop the turbine and there is no airflow.
Old 05-28-2018, 10:34 PM
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I fly this one for over 1 year now
0 problems. , get some BVM heat shield and paint just the top of the cowling.
its fine after this.
it likes the CG a little aft , fantastic wheelys.
Old 05-29-2018, 01:02 AM
  #29  
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Originally Posted by digitech View Post
I fly this one for over 1 year now
0 problems. , get some BVM heat shield and paint just the top of the cowling.
its fine after this.
it likes the CG a little aft , fantastic wheelys.
Thank you for your comment. Which turbine are you using in yours?
Old 05-29-2018, 01:07 AM
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Originally Posted by Neil Guildford View Post

Thank you for your comment. Which turbine are you using in yours?
+1

Cause a turbo prop is on the top of my wish-list i'm really interested in operation/maintenace on this one, is this bird like an "all day" flyer, or is it one that needs tons of looking after and tweaking after every flight?

Thanks,

Ed
Old 05-29-2018, 01:13 AM
  #31  
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Hi Ed its a dailly flyer
mine has a kingtech k45
i fly 10-14 minutes on 1,5-2 liters of fuel.
flies like a cessna trainer.
absolutely easy to operate and no tweaking needed or heavy maintenqnce
Old 05-29-2018, 05:56 AM
  #32  
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https://www.facebook.com/sandor.krui...982831/?type=3

Video pc-21 landing
Old 05-29-2018, 06:26 AM
  #33  
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Originally Posted by digitech View Post
Arggg, don't do Facebook so cannot open the link unfortunately.

But what about the K45TP it self, painless as all the other KingTech turbines?
Have 4 till now and flying the S... out of them and they operate absolutely 100% painless, fuel and go no hassle nothing, just awesome!

I'm a bit worried that the TurboProp could give hassle witch in witch i'm really not interested cause of lacking of time to do all sorts of maintenance.
My birds are made for flying and not for F..... about cause i simply don't got the time for that.

Power wise, is the 45 enough or would you say take the 60?

Cheers,

Ed

Last edited by Midas D.; 05-29-2018 at 06:28 AM.
Old 05-29-2018, 06:33 AM
  #34  
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Originally Posted by Midas D. View Post
Arggg, don't do Facebook so cannot open the link unfortunately.

But what about the K45TP it self, painless as all the other KingTech turbines?
Have 4 till now and flying the S... out of them and they operate absolutely 100% painless, fuel and go no hassle nothing, just awesome!

I'm a bit worried that the TurboProp could give hassle witch in witch i'm really not interested cause of lacking of time to do all sorts of maintenance.
My birds are made for flying and not for F..... about cause i simply don't got the time for that.

Power wise, is the 45 enough or would you say take the 60?

Cheers,

Ed
engine is without any issue , starts everytime
picksup and spools up very fast...
its a no brainer just like the other Kingtech engines
45 is plenty , 60 is a no limits.
if you like sport/scale stay with the 45..
if you want unlimited vertical use the 60..
for me the 45 is spot on , and is relax to fly
Old 05-29-2018, 06:57 AM
  #35  
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Originally Posted by Neil Guildford View Post
Funnily enough, the exhaust angle is bothering me, especially the way one hangs out further than the other due to the offset. Photos would be great!
you can shorten the other ;-)
Old 05-29-2018, 11:43 AM
  #36  
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Originally Posted by digitech View Post
My facebook says this isn't available.
Old 06-06-2018, 05:25 AM
  #37  
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A few photos of progress so far
Old 06-06-2018, 09:02 AM
  #38  
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Originally Posted by Neil Guildford View Post
I hadnít really thought about the heat issue as the turbine itself is further back in the nose. Iíll have a think and maybe just monitor it when I first run it up.
I had the skymaster pc-21 with KT-60, you're gonna cook that wood thats at the back (or front with it backwards ;-). )of the turbine... the gearbox glows red at night time.... heat shield the **** out of the front of this plane.
Old 06-15-2018, 10:16 AM
  #39  
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I ran the Kingtech 60TP for the first time today and it started and ran without any issues.
A problem that has become apparent is the amount of heat hitting the top of the right wing. At idle it reaches just under 100c. At higher prop speeds this reduces slightly to around 80c. Iím thinking the only way around this is to aim the exhaust down more, but not sure.
Another issue is the top of the cowl gets very hot after shut down, even after 3 coats of heatshield paint it needs a leaf blower on it for a minute to prevent it sagging.
Just these issues and the radio to program and itís flying time.
Old 06-15-2018, 11:26 AM
  #40  
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Just a thought Neil. Would it help if you make a wooden partition that "sits" on the fuselage deflecting the hot air from the wings. Then remove prior to flight departure. The wings should be cooler than as when flight takes place the air and propwash should dissipate the hot gases. Re-apply when the plane is again stationary.
As an aside, I often wonder what is the side and downthrust on these planes? Judging from the photos there seem to have quite a deflection.

Reuben
Old 06-15-2018, 12:55 PM
  #41  
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I agree that in flight it will improve, but I would like to reduce the heat whilst itís on the ground as the covering is already showing signs of wrinkling.
A problem with a deflection device is it wonít protect the model as it taxis to and from the runway...I could always follow it with my leaf blower
Old 06-15-2018, 09:09 PM
  #42  
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its a Oracover plane it will wrinkle even without the exhaust heat ;-).
dont worry so much , the heat is normal and you will suffer also from the "oanda"effect where the heat is drawn towards to fuselage in flight.
so slowly after time you will see some discolour comming.
as for the cowl ... yes it gets hot.
i always keep a high idle on the ground , and just before turning engine off , i spool up to 25% then turn it off , it will cool down much quicker.
get that bird in the air!... ;-)
Old 06-15-2018, 09:25 PM
  #43  
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try this youtube video :
video of Landing and a wheely ;-)
Old 06-16-2018, 02:40 PM
  #44  
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I know it won’t look scale, but what about applying some heat reflective tape (I’ve seen it in gold color) to the wing in the heated area, to protect the film covering?
Old 06-18-2018, 07:29 AM
  #45  
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After comparing the angle of the pipes on both sides I realised the right side was angled slight down. Taking into account the prop wash, Iíve adjusted this to now sit slight up and the heat to that wing is greatly reduced.
Attached are a few photos of the cowl locks Iíve used to secure the canopy.

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Old 06-18-2018, 07:38 AM
  #46  
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those locks are nice and better then those screws!
where did you get them?
Old 06-18-2018, 09:34 AM
  #47  
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Old 06-22-2018, 01:29 AM
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The maiden flight was carried out successfully and five further flights on the same day.
The power from the k-60 TP is a very good match but there is an issue withthe idle thrust being too great with the 24x22x3b. I tried lowering the rpm settings on the Kingtech but this resulted in shutdowns when running up from idle so I set it back to 55,000. At idle, the model will move forward, which also causes problems bleeding off speed on landing approaches.
The cowl was still very, VERY, hot after shutdown and the five coats of BVM heatshield paint had blistered away from the cowl and was hanging like a balloon in one section. Iíve added some inlet scoops to assist as air out shouldnít be an issue with that provided by the large nose gear opening.
A friend who wasnít familiar with video cameras captured some footage of the 2nd flight which I will upload later.
Old 06-22-2018, 01:36 AM
  #49  
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Get a Ramoser prop , out performes everything...
5 blade and scale and you can set pitch , engine runs cooler , and more torque.

this thing can really go slow , make sure your CG is correct. on the tube or just in front.
set flaps at maximum , use Crow like i did , raise Ailerons 10mm each side.
even with 25% throttle i can set it down with less then 30kmh ...
you can see in my video thats with 25% throttle..

BTW : Did you open the cowling on the underside? where the wheel retract sits? this makes a HUGE difference.
you need to draw the heat out of somewhere.

Last edited by digitech; 06-22-2018 at 01:39 AM.
Old 06-22-2018, 02:09 AM
  #50  
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No, I haven't cut the underside of the cowl because I couldn't see how air was getting past the turbine from here. Can you please show me where you cut yours?
Are you using the K-45? Do you think this might be why I am having the extra heat issues?

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