HSD F-16 105mm EDF Jet

[Porkster]

Yesterday I removed the old gyro and set the CG for 178 by placing the Rx battery under the electronics bay hatch then added a mix which adds down elevator with extended gear, giving a more nose down/neutral stance once trimmed for flight. The shift in CG when the gear moves is quite significant. This once you've trimmed for level flight make the plane pitch up when you lower the gear. My personal preference is for a little back pressure when landing on the elevator stick not having to push forward.
I've also reduced my rates and expo. Like you Aros, I'm waiting for good weather. Took it to the field this afternoon but it was gusting upto 31mph so it went back in the car again!
shame as I'm going to unable to get to the field for a couple of weeks now.

[Aros]

So with the CG at 178mm with the gear down it shifts aft when the gear is retracted? I thought it was the other way around (gear shifts forward when retracted creating a nose-heavy CG?)...Either way a mix with retracted gear sounds like a good idea.

[Porkster]

exactly as you said, the plane gets nose heavy with gear up.
I initially set my elevator at neutral at 178 gear down but as the gear extends it adds down elevator as I'm going to be adding up trim in flight with the gear up due to its nose heavy in flight. so it should keep it level at all times.
I was very nose heavy on my first flights with this one, I've checked and double checked my CG for exactly 178 so am looking forward to trying it.

[Aros]

Good luck my friend. As we see, this one takes some real research to crack her code.

[Aros]

Looks like maiden is tomorrow. Weather looks sunny for the first time since 1912.

Going to try out my new RunCam camera. Looks like really nice quality HD 60fps. Going to top off my batteries and get this girl in the air!

Anybody have this month's Model Airplane News? There's a really good article about throws and expo that really hit home to me. Truly changes the paradigm of how I've been setting up my rates and expo over the years. In a nutshell, less expo is better than a lot of expo. I used to think the other way around. It would also explain - in part - some of the problems I was encountering with this jet. This is all in line to what Andy of RCJetwerx told me. So no more 40% expo. Hello 15-20%.

If you get a chance check out the article it's one of those "hand slap to the forehead" articles. At least it was for me.

(And now that the cat is out of the bag I can't wait to get my hands on our F-4D Phantom II! Been waiting YEARS for a Phantom this size and quality!)

[Porkster]

Looks like the weather might hold up tomorrow and I'll get another chance to try the Artic camo F-16. I'm moving the CG back to factory and I've added me gear to elevator mix.
I've also done some more to my original F-16 project.

[Aros]

Great good luck! That reminds me I need to still do that elevator/gear mix as well. I've had two flights on mine with the Cortex gyro. That gyro is awesome. I have my CG at 175 and I may keep it there...Just bought some Roaring Tops 5500's I can't wait to try them out to give her a much needed boost. Eventually I will invest in a new power system...Stock is too "meh" for me, especially at her size and weight.

[Porkster]

Success! At last! Thank god lol
first flight was nearly a total disaster, as I rotated I relaxed the elevator and spat! Down she came lucky I kept my nerve and powered on and back up on the elevator as I was headed straight into the rough at the end of the runway.
It was really sketchy and felt like the batteries were moving and changing the CG. Never even tried to raise the gear. Got her back down which again luck was on my side. Thought that the throttle mix may have some how turned back on?
Checked everything back on the ground and all looked ok. Gear survived and batteries were where they should be? No throttle mix?
Not sure I like the resolution of the new elevator servos and the fact I’d turned the expo down too.
I went for another flight and turned the expo up quite a bit and reduced the throws a bit more.
Success, it seems this new version is more sensitive on the elevator than the V1
I'm not happy I had to add a little up elevator even at this CG but it flew well and tracked nicely. Got a decent flight in and the gear to elevator mix worked well too.
I do have a Cortex gyro I could try but wanted to get the basic flight sorted first.

Happy again.
I might even try a little further back to reduce that elevator trim.

[Aros]

Good to hear! This jet has a way of putting our hearts in our stomach that's for sure! Glad you got it sorted out for the second flight. I haven't noticed any extra elevator sensitivity on mine. Maybe the Cortex dampened that? However, if you are flying at 178mm CG that could contribute to the sensitive feeling elevator...Rotation and landings are easier but the elevator is more responsive feeling. Just a thought. I flew my first one at 165mm and while rotation and landings where more of a challenge, she was definitely easier to tame in flight mode for me...But at 175mm I feel pretty comfortable there. Are you flying off pavement or grass?

[Porkster]

Off pavement Aros, you will understand how happy I am to finally get decent flight out of this one. I'm looking forward to the next flights.
Considering I haven't flown my original F-16 in a while this felt reasonably quick, but it really does like to keep the speed up during the turns. I landed a little hot on my 2nd flight but it was smooth touch down. Mainly due to almost zero wind.

[Porkster]

Oh and to add it was a balmy 10*c here today and the gear was still very stiff. I can not express enough that I really dislike it. In the summer it might be OK but here in Suffolk I'll be lucky if it see's over 25*c for more than a few days. I guess the average temperature of only 15* - 18*c and they will still be too hard.
Annoying that I need to find a suitable grease or oil of a lighter weight!!!!!:Angry:

[Aros]

What batteries are you using? I have been flying with Admiral 5000's but one pack is a lot older than the other and I think it's a big contributing factor to the sluggish performance so I have grounded the F-16 until I can get two Roaring Top 5500's. I bought one already but I have to wait until my next payday to order the other.

LOL

[Porkster]

I use either Optipower 5300 which are very good, and zippy compact 6200 40c. Those zippys have really surprised me, they've been pretty good and have reasonably low IR. The Zippys and Optipowers are the same weight which saves any fuss at the field so both fit in the same location up against the bulk head between the battery bay and the electronics bay. I'm using a 2s 3400 for the electronics which is velcro'd and strapped to the underside of the electronics hatch.

[Porkster]

Some small progress on my V1 :)

[Aros]

Looking good! :Cool:

[Porkster]

Thanks! Lots more to do, progress is a little slow at the moment!

[TiredIronGRB]

What batteries are you using? I have been flying with Admiral 5000's but one pack is a lot older than the other and I think it's a big contributing factor to the sluggish performance so I have grounded the F-16 until I can get two Roaring Top 5500's. I bought one already but I have to wait until my next payday to order the other.

LOL

Are they the new style Admirals?

[Aros]

One is the new gen...The other older pack is not. I probably have over 100 cycles in the old one. Time to put it out to pasture I think.

[TiredIronGRB]

There's a world of difference between the old style and new style, I also like the side of the new ones.

[Aros]

Yes agreed...I like the slimmer 5000's...So far so good!