Official Freewing 90mm F-16 Falcon Thread

[Hugh Wiedman]

I’ll check the elevators again but they looked pretty close to equal. I run 20% expo and used book high rates.

That should be just fine then. Can't image why the flight ended up so wonky. May want to fly it next at low rates and see if it is less of a handful, but honestly can't image why it acted so erratic. I'm all out of possible issues, hope someone with a lot more knowledge than me weighs in with some thoughts. How did it handle before you put the Hitec servos in, although I definitely can't believe those changed the flight characteristics so much, should have been a definite upgrade.

[dsmithwc04]

Hmm, I’ll see what I can figure out and report back.

[dsmithwc04]

Looks like I somehow deleted the elevator up mix on the left elevator channel while landing gear are deployed. The elevators were causing a roll that was creating all kinds of havoc while flying. Since I immediately made plans to bring her back around and get her back on the ground I never retracted the landing gear otherwise it would have been obvious that the issue was only happening with landing gear deployed. Yikes, that was lucky I got her down with no damage.

[Hugh Wiedman]

Looks like I somehow deleted the elevator up mix on the left elevator channel while landing gear are deployed. The elevators were causing a roll that was creating all kinds of havoc while flying. Since I immediately made plans to bring her back around and get her back on the ground I never retracted the landing gear otherwise it would have been obvious that the issue was only happening with landing gear deployed. Yikes, that was lucky I got her down with no damage.

Instead of putting a mix in for elevator with the landing gear deployed (or especially when using flaps), I found that by using Flight Modes you are able to trim the elevators in flight at each condition of gear up/gear down (or even better when using flaps, trim separately in flight for each flap position of flaps up/take off flaps/landing flaps). You can do this if you have a Spektrum TX (not sure about Futaba and if I remember I thought you said you were using Futaba). All you need to do is enable Flight Modes (FM) in the TX menus (2nd menu on Spektrum) and assign it to a switch, in your case the 2 position gear switch (I usually do it with the 3 position flap switch). Then go to trim utilities and enable elevator to FM. I also enable aileron to FM in case the flaps do not deflect the exact amount then I can keep it level. Now when you fly with the gear down, you can trim the elevators for level flight, then when you raise the gear, you can trim that configuration for level flight so it's solid at both conditions. Doing it with a mix involves guessing how much trim you need on the ground, taking it up, checking it, then landing and adding/reducing trim, taking it up again, and so on. With Flight Modes you do it once, in the air for each condition and you're done and it's exactly the way you want it, no guess work. Any changes in subsequent flights, like different battery locations, wind conditions, heat/humidity, etc., you are always able to trim it immediately while flying and ending up with a level aircraft. Easy Peasy!

IMO, this is the single best TX programming tool, makes flying just a little less stressful.

[dsmithwc04]

I have a Radiomaster TX16S using openTX. 6 flight mode buttons I've not bothered to use but you have a pretty darn good point.

[Hugh Wiedman]

I have a Radiomaster TX16S using openTX. 6 flight mode buttons I've not bothered to use but you have a pretty darn good point.

A top pilot at our club showed this to me several years ago and now I'm hooked on using it, simple to set up and makes trimming your aircraft perfectly for any configuration in flight on the maiden. No more guess work with mixes or with guessing how much elevator compensation to put in on the flap set up menu as I also use flaperons on my F-16 (which you can still use those mixes as a starting point). And I have to admit that even after the initial trimming, I find myself occasionally fine tuning it every 5-10 flights as weather conditions may change (seems hot humid days vs dry cooler days sometimes affect the orientation), I try different batteries and may not have the same CG or I even play around with the CG, and sometimes I may fly with extra ordinance or non at all, so all that may change how it flies. With the ability to trim in flight at the beginning of the sortie, it's locked in for the rest of the flight and the whole day, no matter what configuration you are in. All of our large turbine pilots and large scale warbird pilots use it (primarily because their aircraft has flaps), and I'm trying to get all our foamy electric guys with flaps to use it as well.

[Aros]

Hugh Wiedman showed me how to use FM's and it changed everything. SO handy, so much more intuitive. A hoist of favorite beverage to you Hugh!

[Thoemse]

I got a hacker streamfan 1200kv 10S lying around. Is it a crazy idea to put it into an ARF F16 using2x 4000mah Lipos. Battery weight: 950 grams.
Is there enough room and is it possible to achive the COG or is it simply a bad idea? The streamfan has a heavier motor than the typical wemotec fan so that would change the COG a bit too.

[Hugh Wiedman]

I got a hacker streamfan 1200kv 10S lying around. Is it a crazy idea to put it into an ARF F16 using2x 4000mah Lipos. Battery weight: 950 grams.
Is there enough room and is it possible to achive the COG or is it simply a bad idea? The streamfan has a heavier motor than the typical wemotec fan so that would change the COG a bit too.

I know virtually nothing about the differences in certain EDF fans, but if you can get enough thrust out of that fan, I believe the batteries will fit and the weight shouldn't be a problem. The HobbyStar 8000 mah battery I'm using weighs 910 grams and the dimension is 43mmX68mmX135mm (wxhxl). The 135 mm length still leaves a good 30-40 mm in the cockpit to move it, but the width of 68mm is to the edge of fuselage wall so nothing wider and the height of 43mm is about maximum as well.

Have no idea if the fan will fit in either. I will tell you that the 6S 12 blade inrunner fan I'm using is a 4068-1835Kv motor. So I wonder if the 1200 Kv motor will give enough thrust, but as I said, I have no idea what the thrust comparison of an 10S 1200 Kv fan would be compared to my 6S 1835 Kv fan, but my first thought is that the Hacker would not provide as much thrust simply because the Kv is so much lower (unless maybe if its something like a 16-18 blade fan).

[Thoemse]

I know virtually nothing about the differences in certain EDF fans, but if you can get enough thrust out of that fan, I believe the batteries will fit and the weight shouldn't be a problem. The HobbyStar 8000 mah battery I'm using weighs 910 grams and the dimension is 43mmX68mmX135mm (wxhxl). The 135 mm length still leaves a good 30-40 mm in the cockpit to move it, but the width of 68mm is to the edge of fuselage wall so nothing wider and the height of 43mm is about maximum as well.

Have no idea if the fan will fit in either. I will tell you that the 6S 12 blade inrunner fan I'm using is a 4068-1835Kv motor. So I wonder if the 1200 Kv motor will give enough thrust, but as I said, I have no idea what the thrust comparison of an 10S 1200 Kv fan would be compared to my 6S 1835 Kv fan, but my first thought is that the Hacker would not provide as much thrust simply because the Kv is so much lower (unless maybe if its something like a 16-18 blade fan).

It is really about size for the lipos and COG. Thrust is no issue. It's delivering 4.4kg of thrust. From experience the thrust of wemotec fans is thrustworthy and not as "optimistic" like chinese competitors are. If the lipos fit it should be a rocketship with that edf.

I'll check the dimensions. Weight seems to be no problem.

[Hugh Wiedman]

It is really about size for the lipos and COG. Thrust is no issue. It's delivering 4.4kg of thrust. From experience the thrust of wemotec fans is thrustworthy and not as "optimistic" like chinese competitors are. If the lipos fit it should be a rocketship with that edf.

I'll check the dimensions. Weight seems to be no problem.

Agreed, with enough thrust, weight is definitely not a problem with this airframe (although some complain that it flies "heavy" but I think that is with the original stock outrunner fan-at least the 12-blade inrunner has plenty of guts and I don't feel that it flies "heavy" at all, even with a battery of over 900 grams). I have no idea how much actual thrust the 4068-1835 KV inrunner has but RC Castle measures it around 4.0kg, so if that is "optimistic", then the 4.4kg for yours sounds impressive and should indeed work great. I'm flying mine at a CG of 126 mm with the gear down (back a bit from the 118mm the manual suggests). The battery bay without any trimming will accommodate something of 68 mm wide, by 45-50mm in height and a length of 210 mm. However, at that length of 210 mm you won't have much room to move the battery to affect the CG. With the 8000 mah battery I use, I've got about 10 mm I could move it further back, or 65 mm I could move it forward to adjust the CG. Hope these measurements help.

The only video I have of my F-16 in the air is attached, with the first flight on an HRB 6000 (weight 825 g) and the second on the heavier Hobbystar 8000 (weight 910 g). You can see that the take off run is virtually the same and that extra weight has no affect, as long as you have enough thrust from a decent EDF. Both flights were balanced at 120mm and since those flights, I've moved it back to 126 mm and it flies even better.

[Mizer67]

My 1835kv 90mm from FW measured 3,300 grams of thrust when installed in the F-22. 4,000 grams outside of the plane I would expect to be possible.

Not sure of the F-16's AUW, but the F-22 at ~3700 grams flew very light and had great vertical with that motor.

[Thoemse]

Agreed, with enough thrust, weight is definitely not a problem with this airframe (although some complain that it flies "heavy" but I think that is with the original stock outrunner fan-at least the 12-blade inrunner has plenty of guts and I don't feel that it flies "heavy" at all, even with a battery of over 900 grams). I have no idea how much actual thrust the 4068-1835 KV inrunner has but RC Castle measures it around 4.0kg, so if that is "optimistic", then the 4.4kg for yours sounds impressive and should indeed work great. I'm flying mine at a CG of 126 mm with the gear down (back a bit from the 118mm the manual suggests). The battery bay without any trimming will accommodate something of 68 mm wide, by 45-50mm in height and a length of 210 mm. However, at that length of 210 mm you won't have much room to move the battery to affect the CG. With the 8000 mah battery I use, I've got about 10 mm I could move it further back, or 65 mm I could move it forward to adjust the CG. Hope these measurements help.

The only video I have of my F-16 in the air is attached, with the first flight on an HRB 6000 (weight 825 g) and the second on the heavier Hobbystar 8000 (weight 910 g). You can see that the take off run is virtually the same and that extra weight has no affect, as long as you have enough thrust from a decent EDF. Both flights were balanced at 120mm and since those flights, I've moved it back to 126 mm and it flies even better.

That video shows me just what I needed to know. We got a fantastic flat tarmac track with our club. The one thing though: It is 70 meters long. Land to soon and the plane will shatter, don't come to a halt after 70 meters it is either going into our "natural fence" wich is not mowed grass 1m high, or roll to the side into bumpy but mown grass. With jets that usually kills the front retract.
Watching your landings was very helpful in my case because it looks like it can be landed slow and high alpha. I got a 90mm Flyfly mirage 2000 that UI can land just fine on this track. Some jets are out of the equation though because of high landing speed.

[Hugh Wiedman]

That video shows me just what I needed to know. We got a fantastic flat tarmac track with our club. The one thing though: It is 70 meters long. Land to soon and the plane will shatter, don't come to a halt after 70 meters it is either going into our "natural fence" wich is not mowed grass 1m high, or roll to the side into bumpy but mown grass. With jets that usually kills the front retract.
Watching your landings was very helpful in my case because it looks like it can be landed slow and high alpha. I got a 90mm Flyfly mirage 2000 that UI can land just fine on this track. Some jets are out of the equation though because of high landing speed.

Great, glad to help. Of course not all of my landings are always like that, but the F-16 will slow down nicely and easily get into a somewhat high alpha for landing. Obviously on a nice flat tarmac your take-off distance will be even shorter. You should also keep in mind that I set mine up with flaperons, primarily to help get off the grass, with deflections for take-off flaps at about 16 mm and landing flaps about 22 mm. These are relatively minor deflections for flaps, but I obviously did not want to over extend my aileron servos and kept them rather tame. This helped getting it to slow down a bit, so you might want to give flaperons a thought since your runway length is minimal. A nice 5-10 mph headwind also does wonders for take-off and landing!

[gooniac33]

Haven't flown mine in a while... time to take it out this weekend!!

[Aros]

Mine smashed into a tree on takeoff (don't ask lol) and came straight down and plunged the nose cone completely into the grass! The front of the fuse is busted up pretty good but with some goop, sanding and painting I think I can avoid needing a new fuselage. I have a spare nose cone and I will need to buy a new cockpit but the good news is the entire rest of the bird was untouched, gear and all. I'll start the repair project this weekend.

[Mizer67]

I have one spot on the wall left to use and have been eyeing this plane for a while.

Trying to pull the trigger on either it or the Phantom.

Can anyone tell me an accurate empty weight? Concerned it's too heavy to perform very well.

[Aros]

It's too heavy with the old outrunner setup it used to come with. Now with the High Performance inrunner version it flies great. Still a heavy jet (the older FW jets were heavier in general than the newer gen models) but with the proper power setup it flies like it should. If you're still concerned about AUW the F4 and F-22 are outstanding jets in presence, size, performance, and being lightweight (comparatively-speaking).

[Mizer67]

Yes, I have the F-22 and still think it's the best performing 90mm jet out there. In 90mm, I have the F-18 also and it is great too. Different but great. It's ~2800 grams empty and flies fine at that weight with the stock 6S 1900kv setup.

I flew the 90mm F-16 ~5 years ago and thought it was significantly underpowered and piggish as a result. I still want an F-16 though and after owning the 70mm E-Flite, wasn't impressed. People love them but mine never flew well. I find I fly my 90mms more lately and find myself liking the larger format, but am not quite ready to step up to the HSD F-16.

[Aros]

...but am not quite ready to step up to the HSD F-16.

Either am I and I have had 3 of them!