Habu STS

[Dougf]

Hi all,
A few notes from the maiden yesterday, with thanks to Mike, Hector and Robert for their assistance.

The plane is a PNP, and I installed an Admiral rx with gyro stabilization. Went with a 3S 3200 for the first flight, well balanced to the right CG with the battery full forward. The rx has 3 gain pots for stabilization around roll, pitch and yaw axes, and I rolled the gains back about 30% from maximum. This was way too much gain! After takeoff the plane oscillated in roll a lot, making it very hard to control the plane, but managed to get it back on the ground.

The clevis pin on the nose wheel broke off and had to be replaced, luckily Hector had a spare in his tool box. The clevis needs to be metal type, otherwise it will keep breaking.

Turned the gain way down, maybe 20 or 25% above zero, took off again and flight went much better, plane probably doesn't need any gyro at all.

The other thing that happened on both flights was that the throttle cut out at max throttle about 20 seconds after both takeoffs. Power returned by pulling back on the throttle a bit each time. There's lots of comments on RCGroups about this and basically this points to hitting LVC and/or voltage sag due to a weak battery. Apparently a battery that is perfectly good on a prop plane may not be up to powering an EDF. I have some new Admiral 4S 4000MaH 40C LIPO's that hopefully will do the trick.

Other than that, looks like a nice plane to learn how to fly EDF's and get up to speed for the Avanti.

[Dougf]

Here's an update for anyone interested:

I flew the Habu yesterday with a new freshly charged 4S 4000 40C battery. Nice smooth flight except that the same thing with power loss happened at least 3 or 4 times during the flight. The power loss usually lasted a few seconds, during which the plane would start to descend, and then it would recover power. Not a recipe for safe flying! I decided to take the plane home in one piece after just the one flight and to look into the power loss in more detail.

Turns out fail safe mode which is triggered by signal loss results in throttle being reduced to low power. I have a new Admiral RX600 stability gyro receiver in the plane, with antenna's properly oriented at 90 degrees from each other and away from obstructions. A range test was done before first flight, so it appears the problem is an intermittent receiver. I called Motion RC today, went over the whole installation and they agreed it was probably an issue with their receiver and are sending me a replacement right away. Great customer service!

Hope this is info is helpful, please let me know if any comments or questions.
Doug

[Michael O'Bree]

Very interesting - thanks for sharing Doug.

I have added some tags to this thread to help people find the info. by searching the website if they have similar symptoms.

[Mezri]

Hi Doug, congratulation for the habu ,...Is your ESC well ventilated, with the heat sink facing open air (Not glued on surface) ? An ESC with bad cooling can cose cutoff because of over heat.

[pauldaigle]

Just a thought, but several people have reported a dead zone area approx. 100 yards east of the field that could be caused by the Cell tower nearby. They also seem to have added 5G elements to the tower lately. Don't know if your receivers front end can be affected by same. Maybe someone with more knowledge of RFI/ EMI etc. etc. can provide some insight into this. Thank you.

[Dougf]

Very interesting - thanks for sharing Doug.

I have added some tags to this thread to help people find the info. by searching the website if they have similar symptoms.

Thanks for adding the tags Michael

[Dougf]

Hi Doug, congratulation for the habu ,...Is your ESC well ventilated, with the heat sink facing open air (Not glued on surface) ? An ESC with bad cooling can cose cutoff because of over heat.

Hi Mezri, thanks for the suggestion. The ESC installation is the stock setup from the factory, and the plane has vents to direct airflow to the inside of the fuselage. I will have to check how the heat sinks are located. There are a few other folks at the club who have the same plane and setup and I will check with them as well.

I changed transmitters and rebound the aircraft and flew it 3 times today, still had one or two power drops but not as many as before. I'll change out the rx when I get it from Motion RC. Meantime, as long as I stay close to the field it seems relatively safe to fly with this intermittent issue.

[Dougf]

Just a thought, but several people have reported a dead zone area approx. 100 yards east of the field that could be caused by the Cell tower nearby. They also seem to have added 5G elements to the tower lately. Don't know if your receivers front end can be affected by same. Maybe someone with more knowledge of RFI/ EMI etc. etc. can provide some insight into this. Thank you.

Thanks Paul, seems to be happening all over the place. This RFI/EMI stuff is like chasing ghosts! I'm more concerned about the dead zone between my ears when I fly my planes into the trees. :)

[Mezri]

seems to be happening all over the place.

An other reason to think realy about the ESC...Even from factory, I saw many stupidities from factory ...there is one nice flat surface on the ESC, and an other bumpy surface. By reflex, I so many putting the double side foam tape, and glue that surface...Bad...that is the heatsink surfce taht need some air.

Even if your ESC is well positioned, try to exchange it with an other,...in your process "by elimination", it might be faulty.

[Jdonald]

The HABU is available in two versions, the BNF and PNP.
The BNF version is designed to be a easy to fly 1st jet. $399.99 U.S.$
The PNP version is a not so easy to fly 1st jet. $219.99 U.S$
The BNF version comes with a flight controller and serial receiver. The flight controller has the dual diversity antenna. The antenna lead extensions are longer
than say the AR636A receivers.
These foam jets contain a fair quentity of carbon fiber reinforcement. The battery occupies about 25% of the aircraft. As a result there is plenty on board the aircraft to block the signal to the antenna and cause a hold, the receiver moves the channel outputs to the failsafe setting. It is possible your receiver and or setup is not compatible for this aircraft.
However an extensive range test should be done to ensure that signal loss to the receiver is not the cause of the problem before flying.

[Jdonald]

Just to clarify a couple of points, with the BNF version price difference this version also comes with a transmitter, charger and the batteries. It appears this is really designed to be a persons first RC aircraft. Personally I think a Sport Cub-S is a better choice. But if this is what it takes to attract someone to the RC hobby lets hope this approach it the right one.
The second clarification is about the longer antenna leads. The antenna are not longer only the antenna leads. This allows for more flexibility of location and the antenna can be moved further away from objects such as batteries, receivers that can block the transmitter signal.

[raymondb]

From your description of the behavior, I think the ESC programmation is to blame. There are usually two setting:

1- Low voltage detection threshold: can be set to High, mid, or Low. If it is currently set to high, the batteries voltage drop caused by the high current pulled by the motor will cause an early low voltage detection. (it should be set to low)

2- The Low voltage action: When low voltage is detected (see conditions above), the reaction of the ESC can be set to MOTOR CUT (this is probably what you have now) or to REDUCED POWER (this is what you should have).

Most ESC have these two settings available but each brand name and model have their own list of options and programmation mode. You will need to do a search on the web for how to program your specific ESC (brand and model).

[Dougf]

An other reason to think realy about the ESC...Even from factory, I saw many stupidities from factory ...there is one nice flat surface on the ESC, and an other bumpy surface. By reflex, I so many putting the double side foam tape, and glue that surface...Bad...that is the heatsink surfce taht need some air.

Even if your ESC is well positioned, try to exchange it with an other,...in your process "by elimination", it might be faulty.

Thanks Mezri, I'll check that. FYI I changed from a DX9 to a DX6e transmitter yesterday, no power loss. Very strange.

[Dougf]

The HABU is available in two versions, the BNF and PNP.
The BNF version is designed to be a easy to fly 1st jet. $399.99 U.S.$
The PNP version is a not so easy to fly 1st jet. $219.99 U.S$
The BNF version comes with a flight controller and serial receiver. The flight controller has the dual diversity antenna. The antenna lead extensions are longer
than say the AR636A receivers.
These foam jets contain a fair quentity of carbon fiber reinforcement. The battery occupies about 25% of the aircraft. As a result there is plenty on board the aircraft to block the signal to the antenna and cause a hold, the receiver moves the channel outputs to the failsafe setting. It is possible your receiver and or setup is not compatible for this aircraft.
However an extensive range test should be done to ensure that signal loss to the receiver is not the cause of the problem before flying.

Hi John,
Thanks for all your comments. I bought the PNP version for 2 main reasons. Firstly I didn't want another transmitter and all the automation gizmo's and secondly, I wanted a bit of an easier EDF to learn on before going back to the Avanti with its retract gear and flaps.

I put an Admiral 6 channel rx in it that has a stability gyro, which helps this light jet in turbulence. I agree with your comment that the PNP is a "not so easy" jet to fly. Meanwhile I bound a DX6e to the rx yesterday, as I saw a YouTube video where the guy had reception issues with a DX8 which went away when he switched to a DX6. Lo and behold, my flights yesterday were without power loss.

Had a helmet fire on my second flight, came in too slow on one of my approaches, stalled a wing and it rolled over and hit the ground. a couple of clean breaks, so not too serious, but its an important lesson to keep speed up and flowing over the control surfaces on EDF's. There's no prop wash!

[Dougf]

From your description of the behavior, I think the ESC programmation is to blame. There are usually two setting:

1- Low voltage detection threshold: can be set to High, mid, or Low. If it is currently set to high, the batteries voltage drop caused by the high current pulled by the motor will cause an early low voltage detection. (it should be set to low)

2- The Low voltage action: When low voltage is detected (see conditions above), the reaction of the ESC can be set to MOTOR CUT (this is probably what you have now) or to REDUCED POWER (this is what you should have).

Most ESC have these two settings available but each brand name and model have their own list of options and programmation mode. You will need to do a search on the web for how to program your specific ESC (brand and model).

Hi Raymond,
This is really helpful, thanks. I'll check into it and see what needs to be changed in the ESC programming. Meantime I have some foam gluing to do thanks to a rollover yesterday. I'm also going to log a few hours on RF9.5 with the wind turned up before I fly it again. See you soon. Doug

[Jdonald]

Sorry to hear about the damage to your plane yesterday. But you are a seasoned flyer and know that planes are easy to damage. You know that repairs are part of this hobby. I mentioned the price comparison between the two versions as the complete package appears to be directed towards someone trying to get started in this hobby. Imagine someone new to this hobby paying $600 Canadian and doing extensive damage on the very first flight. RC Geek has a video where his son with very little experience flys the Habu and the father calls it a success. But the father talked him through how control the plane and guided him on the landing. The plane was damaged and in need of repairs. $600 for one flight might be a turnoff someone new to the this hobby. However at WIMC we are lucky to have Raymond B. to guide us on how handle these jets.

[Dougf]

Sorry to hear about the damage to your plane yesterday. But you are a seasoned flyer and know that planes are easy to damage. You know that repairs are part of this hobby. I mentioned the price comparison between the two versions as the complete package appears to be directed towards someone trying to get started in this hobby. Imagine someone new to this hobby paying $600 Canadian and doing extensive damage on the very first flight. RC Geek has a video where his son with very little experience flys the Habu and the father calls it a success. But the father talked him through how control the plane and guided him on the landing. The plane was damaged and in need of repairs. $600 for one flight might be a turnoff someone new to the this hobby. However at WIMC we are lucky to have Raymond B. to guide us on how handle these jets.

Thanks John. I saw that RC Geek video and it struck me as a promo for the product. Some of these YouTube reviewers are a bit biased in their reviews it seems. I noticed when his son landed the Habu, it did a good bounce, and the nose wheel was turning loosely when his Dad picked up the plane. Must have broken the clevis pin like I did. Anyway, my bird is almost back in flying shape, will post a pic when it's airworthy. Cheers.

[Jdonald]

Hi Doug,
Check this Video "Flight Habu STS Perfect RC Smart Jet for Beginners"
It is 11:18 min
It is about 3 persons assembling the Habu and first flight. Near the end of the video they mention there was some problem similar to what you experienced when using a DX8 transmitter. When a older 7 channel transmitter was used the problem did not arise.

[Dougf]

All foam tac'd and ready to go. Just need to check the ESC programming and fly the sim a whole lot more. Looking at the forecast, add ski's??

[Dougf]

Hi Doug,
Check this Video "Flight Habu STS Perfect RC Smart Jet for Beginners"
It is 11:18 min
It is about 3 persons assembling the Habu and first flight. Near the end of the video they mention there was some problem similar to what you experienced when using a DX8 transmitter. When a older 7 channel transmitter was used the problem did not arise.

Hi John,
That's exactly the video I was referring to in post #14 above! I switched from a DX9 transmitter(recent vintage) to my original DX6e transmitter about 3 years old, and presto, the problem went away. Go figure. CU soon. Doug

[Dougf]

From your description of the behavior, I think the ESC programmation is to blame. There are usually two setting:

1- Low voltage detection threshold: can be set to High, mid, or Low. If it is currently set to high, the batteries voltage drop caused by the high current pulled by the motor will cause an early low voltage detection. (it should be set to low)

2- The Low voltage action: When low voltage is detected (see conditions above), the reaction of the ESC can be set to MOTOR CUT (this is probably what you have now) or to REDUCED POWER (this is what you should have).

Most ESC have these two settings available but each brand name and model have their own list of options and programmation mode. You will need to do a search on the web for how to program your specific ESC (brand and model).

Hi Raymond,
Quick update...HH agreed that the ESC was at fault and sent me a free replacement. It took awhile to arrive, but it was worth the wait. The new ESC has fixed the issue and I have flown several flights now without any throttle or control interruptions. Thanks for your suggestions. Recent picture attached.
Doug