Helijet

Hey Digital Pilot

I just ordered the Thunderbird version from Dirk. Hope to have it by next week. I have a K60 already so looking forward to putting the package together. sounds like careful note of CG and removal of funky elev/throttle mix have been hot topics.

Looking forward to sharing notes...

Dean W.

Digital Pilot

CG and removal of funky elev/throttle mix have been hot topics?

Can you elaborate....

Thanks

Helijet

I have been following the HSD turbine F16 in the digital world for several month now. First off the turbine version is different than the EDF one in foam density and parts quality - which are good things. Those on Facebook and other forums that have built and flown the turbine version noted that the F16 has a bucking bronco tendency on final approach. It appears that the initial recommended CG was too far aft ( 200 mm ) which would explain this. There was considerable discussion around the need to mix elev / throttle mix but there was confusion around whether down mix or up should be applied. Having flown F16 models for decades I know from experience that the bird is sensitive to rapid throttle input and yanking on the elev. Lately, those that have been successful are indicating the now recommended tank empty, gear down UAT full CG of 180 - 185 is a good starting point. Mixing is not needed and some have started playing with flaperons.

The info so far...

dw

Digital Pilot

Ok great.. Was hoping to get a little info. Was thinking of flaperons as well.

Thanks for the info

LA jetguy

I maiden the Super Viper today.... It just needed two clicks of up elevator and it was flying very nice. I had seven flights in a two hour period. I hot fueled two times and changed the turbine battery (3 cell Lipo 2100) after the forth flight.

The fuel tank capacity is a little too small for my taste with K60. My timer was set for 5 minutes at 1:30 I geared checked and landed at times up. I had less than 1/4 fuel left in the tank. I admit I run full throttle most of the flight. I'm thinking of using the smoke tank to increase fuel onboard.

After 4 flights I checked the controls battery (using 2 X 2 cell Lipo 2700) and they were at 89%. I was very happy about power consumption. The brakes were working evenly and smoothly.. no lock ups.

All in All... "EXTREMELY FUN" and ENJOYABLE.

David

oukenfold

Hey LA jetguy some questions for you.


1.- how many channels did you use, because you use cortex gyro y read somewhere you need 2 channels for this gyro.

2.- did you program some flight modes in your transmiter meaning did you trim up when you use flaps o you let the gyro stabalized the plane for you?

3.- do you recomend more mah 3s life for the turbine like maybe 3000 mah?

4.- do you have videos of the maiden?

5.- did you first test bench your turbine befero you instaled un the jet?

6.- so combined the fuel tank and smoke tank maybe i will get 8 to 9 min flying?

thanks in advanced

LA jetguy

1. You need total of 7 channels. The elevators, ailerons, flaps and Rudder (connected to steering) are all Y'd. The elevators, ailerons and rudder get plugged into the cortex pro and the one wire from serial out out of the receiver (I'm using Jeti REX12) plugs into the cortex pro serial input. I tapped into an open port from the receiver to give more power (if needed) to cortex pro. Note that the receiver is back powered from the other servo connections such as retracts, brakes, smoke, turbine. So no direct power is connected to the receiver

2. Yes I use flight modes and I have different gyro gain for each flight mode. So trim adjustment is stored for each mode. No aileron adjustment was needed even during flap deployment.. amazingly they were all traveling correctly at each mode. Few clicks of up trim was needed since in my opinion it was slightly nose heavy. I like nose heavy jets at least at maiden and then slowly I move CG back.

3. I recommend a 3 cell 2100 LiFe to keep the weight down for turbine. Kingtech battery is perfect. I use 2 cell Lipo for controls to keep the weight down.

4. No video..

5. No I installed the turbine out of the box into the jet. You just prime the fuel line. I ran the engine a few times before initial flight. Just make sure no air is trapped in the fuel filter.

6. Yes you can... my only concern is excessive weight. I like to fly my jets fast. So weight is a concern. I will do the conversion and treat the smoke tank as an onboard wing tank. Just fill it half way so I burn that fuel till I get to runway...

It's a great jet .. I have a stand I use to transport jets in my suburban and this jet goes in with both wings attached. Just bring out fuel and fly.... its real FUN...

David

oukenfold

LA jetguy first thanhs for your quick response.

i will use a dx9 with a 9 channel receiver, and i see i need 7 channels with out the smokepump, so i have 2 extra channels one for the gyro modes and one for the gain knob. i will use a eagle tree guardian 2d/3d gyro, so i know i can have 3 flight modes with independent trim for each one of my F.modes in my dx9 spektrum, i dont get it how you can ajust gains for each flight mode, i think you have 1.- take off mode, 2.- flying mode, and 3.- landing mode, and you gyro is always on, or how did you make that, because i read that when you put down flaps the jets goes up and you have to use elevator , but in this case you use gyro and the cortex automatic put the jet on level flight.

2.- does the CG its market on the jet?

3.- does the recomended surface travel of the servos are ok or they are to much?

4.- the ubec or power board that came with the jet have a master and a slave input do you use both? i dont get it why its the slave input for? backup only? i read i need a life battery for the turbine, but i can use another lipo 3s forthe power board, i dont know why pacific jet sugest 3 batteries, if with only one 3s lipo connected to the power board give power to everything.

sorry for the bombing questions men but this is my first turbine ever jet.

rhklenke

My Feedback: (24)

So this thread originally started out as a discussion of the new jets that HSD/Pacific RC Jets was doing.

Now that we know that the next one out is the Mirage, and they are not doing the T-45, what IS the next one that they are coming out with, any news?

Bob

Digital Pilot

I heard a rumor of the F-86 Sabre being next.

erh7771

My Feedback: (30)

Same

rhklenke

My Feedback: (24)

That was what Dirk suggested earlier in the thread, but I haven't heard anything about that since.

Personally, I'm not interested in an F-86 as it won't be a good grass field airplane, but I'm also wondering how practical a turbine F-86 will be at this size. It is really hard to get fuel into an F-86 model because of the inlet running the entire length of the fuselage. The word above was that fuel was somewhat of an issue on the Viper and an F-86 is likely going hold less than that, for sure...

Bob

LA jetguy

1. I'm not familiar with Spektrum programming its been a long time since my DX18. I use Jeti DS16/24. Jeti transmitter has a gyro menu which works very well with Cortex (pro).. You can set different gains for each flight mode and I have a switch to turn off gyro (Gain=0). I have 30% for cruise mode, 45% Take-off mode and 55% Landing mode.

2. Yes the CG is marked on the right retract frame. its just in front of the retract frame screw. Mine was initially nose heavy... safe for maiden flight.

3. They elevator seemed good (25mm) but the ailerons (25mm) was too much . I lowered to 20mm on the ailerons. Rudder is good as recommended. Take off flaps at 25mm and Landing flaps at 50mm.. all inboard.

4. I used both power connections for the "Power board" even though during testing I powered one connection and everything turned on. I still like a redundant system so I used both power cord connected to two 2-cell Lipo. The servo connections provide the power to the receiver. Kingtech turbines are happy with a 3cell LiFe battery (2 cell Lipo is OKAY but for two startups only). You have an option to supply the power board with a 3 cell LiFe or 2 cell Lipo. The power board will regulate to 6.05 V anyways (option to 5.0 as well). My idea was heat buildup during regulation from 9.9 to 6 compare to 7.4 to 6... so I elected to use 2 cell LiPo for controls. I plugged a 3 cell LiFe (by mistake - turbine battery) during testing and all was well....

One side note is that the brakes will time-out after 45 sec of being on hold. you need to release the brakes and re apply for the brakes to hold again. I have created a cycling sequence in my Jeti transmitter which will pulse a sec of "OFF" to re set the brakes and keep them on hold as long as my brake lever is on.

You will enjoy the Viper.... It is a FUN jet and very simple to assemble well worth the $$..

David

Eddie P

My Feedback: (4)

Are all the next round of jets (Mirage, F-86, T-45 potentially) also going to be in foam?

Digital Pilot

Kingtech EPO jets by HSD will all be foam as that's what they specialize in. This is what keeps the cost down..

oukenfold

David , question, i see thet when you hit the brakes switch the brakes stop the wheel for 45 sec, why do you need more time? does the jet need more time for brake? or maybe when you are going to takeoff you whant the jet still? i am guessing. can you clarify thanks ,

Digital Pilot

I would think for starting and needing to hold for another aircraft to take off or land.

DUCMOZ

Hi Dean, let us know how it goes. I have been contemplating on this one as I have had a lot of fun with the Converted Stinger for goofing off.

Behzad

jlmaviation

My Feedback: (54)

Skip the F-86. Go with F100

luge_racer

Meaning you refueled while the engine was running? Is that safe?

luge_racer

Darn, I was planning on getting the T-45.

I remember seeing mention of an F/A-18 and video of a hovering J-10. Maybe those were canned too or I'm mistaken.

Desert Fox 1

ELECTRIC BRAKES


OUKENFOLD,
The 45-60 second is a protection feature of electric brake systems. If brakes are applied and no signal change happens for 45-60 seconds they release to prevent battery drain and to protect the coils in the system.

Cheers!
Desert Fox 1

rhklenke

My Feedback: (24)

Me too! I haven't heard about anything new coming out and the T-45 was already flying in the prototype stage - its a shame they don't just finish it up and see who wants one. I think they would sell a bunch here in the US, especially if it was was a true T-45 and it was available at flyins this summer ...

Bob

LA jetguy

Exactly as Digital Pilot and others have said. I set the brakes on during startup and when standing on taxi way waiting to take on the runway. With my transmitter (Jeti DS16/24) i have created a cycling sequencer associated with a switch (parking brakes) which pulses a second of off to re set the brake again...

David

LA jetguy

As long as you do not spray fuel into the turbine it should be okay. I took my Jersey Can to the runway. Once I land I taxi back fuel the tank and on I go... I actually save a lot of turbine battery since I skip the cool down and startup process which consume most of the battery capacity...

David