Hobby King 1875mm B-17G Flying Fortress V2

[davegee]

Thanks, Aros. Oh,yes, I have watched and studied your video several times to learn moer about its flying habits. Do you still have this airplane? Were there any screwy things about it that bothered or concerned you?

Thanks for all the great stuff you do for us modelers and Motion RC fans.

Cheers

Davegee

[davegee]

Yea PROGRESS. Looking good Dave. I am looking at trailers because I can't get enough planes for a day's flying in my truck. Club members have several 10-12' long trailers and they don't have to dissemble them. Might be an option for you
Best Regards,Rex

Yes, a good idea, Rex. Not sure where I would put the trailer when I wasn't using it, though. But I would love to be able to transport all my planes without having to take them apart, like this one, which is going to be a pain to disassemble/reassemble and plug in the leads between the wing and fuse. I've got it down to just 3 connections I have to make to be able to screw it all together and ready for a flight.

Cheers

Davegee

[Aros]

Thanks, Aros. Oh,yes, I have watched and studied your video several times to learn moer about its flying habits. Do you still have this airplane? Were there any screwy things about it that bothered or concerned you?

Thanks for all the great stuff you do for us modelers and Motion RC fans.

Cheers

Davegee

No, I haven't had the model in years. I do remember enjoying her. Loved the size and always wished Freewing would come out with one of similar stature. Once the stock props were thrown in the garbage where they belonged and the MA props were added, she flew great. I do recall her getting bounced around a bit in windier conditions but for the most part she flew well. I think I recall needing a flap/elevator mix to counter the ballooning but I would not be able to remember the mix. I think you will enjoy her at least as much as I did.

[davegee]

I took mine out on the driveway to taxi it around today. Then a big wind came up and the airplane acted like a weathervane and I couldn’t turn it, just had to taxi into or away from the wind. A couple minutes fighting that and it was time to go back inside!

[Aros]

Yep, she's not super wind-friendly, lol!

[davegee]

Yep, she's not super wind-friendly, lol!

I don't know if you watched the great miniseries Masters of the Air, but there is a part where they are ferrying their brand new aircraft to England from the USA, they have to make a fuel stop/layover in Greenland. The crosswinds are hellacious but they have no choice, they HAVE to land! They had to accurately navigate fjords to make it into base. And then they had to fight huge crosswinds without cracking up their aircraft and killing their crews.

I got an appreciation yesterday for crosswinds and heavy winds yesterday just taking my B-17 out onto the driveway. I won't risk much, if any wind flying it, especially when it is new.

For now, I am stuck waiting on an adapter plug to fit in my Spekturm charger and the XT60 plug on my batteries. I've been able to do all my tests so far on the charge that came on them when they arrived from MRC recently. So, I have other detail stuff I can work on while I wait for my battery adapters.

Cheers

Davegee

[davegee]

Afterr mostly getting the propeller selection in place with the MAS propellers, I'm going to take advantage of some down time as I wait for the charger plug so I can recharge my 3S batteries with the XT60 plugs that I don't normally use. One thing I did was confirm that I can get this very large rc airplane into my truck to take to/from the field. I wasn't completely sure until now. It actually fits in better than I thought it would. I put the fuse in the back seat floor with the seats up, and the wing fits well diagonally in the bed. So, that potential problem is solved. Will probably only take that airplane to the field when I fly it, as it will take just a little bit of work to reconnect the four (4) connector plugs and get everything stuffed into the fuse for flight.

I also fashioned a couple of pitot tubes using 1/16 inch diameter aluminum tubes. I ground the tip so you see it comes to a point yet you can still see the tube opening as you would on a full sized one.

Regarding the gear,for now I've decided to stay with the non-scale stock gear struts until I come up with another plan. I actually did make an attempt to lower the strut about 3/8 of an inch, which did work by shortening the steel strut, but the problem arose when testing it that the retract would need to be moved forward a bit to allow the geometry of the gear to retract into the wheel wells ok. But that would involve pulling out the stock threaded plastic mounting tubes and put some hardwood in there to screw down the retracts in the new location. That was more than I wanted to do with this particular airplane model, but I might consider it if I make another one. In any case, even shortening the strut that goes into the retract, the coiled spring would still work as normal, since this plane doesn't have a spring shock absorbing strut. I can always go back and readdress that if I choose.

I'm going to add some scale looking hydraulic lines that run up and down the plastic covering that goes over the steel strut for more realism. The last thing I'm going to toy with is try to come up with some retract/extend fake struts that might make the model look a little more like the real thing, although it still stands too tall on the stock retracts. There is some interesting geometry on how they extend and retract on the real thing, and I'll at least give it a go to come up with something that makes the gear a little more complete looking.

Cheers

Davegee

[jetfool]

Glad it all fits in the truck.

[davegee]

Glad it all fits in the truck.

you bet! I did take a tape measure to my truck before I even ordered this kit. If it didn't fit theoretically, I wouldn't have ordered it. But I am surprised it fit in with inches to spare, so that is a good thing.

Cheers

davegee

[davegee]

Did some simulated brake lines work on the airplane today. Still waiting on parts that come next week to continue work.

I read up on the tires that Boeing settled on for the B-17 back then. They were all a standard 56 inches in diameter,. Later, same-sized tires used on the B-47 Stratojet, B-36 Peacemaker, and B-52 Stratofortress. On the aircraft I'm more familiar with, the Boeing B-747 and B-747-400, the tires were 49 inches in diameter, and the same tires were used for all 18 wheels, including the two nose tires. I thought that was pretty smart of Boeing so you didn't have to have a mix of various sized tires to replace on the road. Any suitable tire would work!

[Elbee]

davegee

BEE-UTE-TIF-FALL !!!!

Best, LB

[Aros]

Nice!!!

[davegee]

It should work, for now. If I find a way to replace those too- high main struts, I’ll do that. We’ll see, a work in progress…

[davegee]

I made up a scratchbuilt scale-looking retraction/extension mechanism to look somewhat like the real ones. I did have a couple of drawings to go by, but it was mostly a try and try again procedure to get the aluminum tubes and Robart hinge pins to work properly through the cycle up and down. Finally got it consistently going for now. More testing needed.

The B-17 also had two struts or drag links shaped in a Vee pattern from the main gear strut that provided additional strength to the gear to keep it from collapsing during takeoffs and landings stresses. I have not figured out how to add that yet to a model airplane so that it fits, but hope to put that in, too, as I continue to work on this. Pretty complicated geometry and fitting the mechanism into a slot next to the wheel and gear strut when it is retracted.

Here's a couple of pics.

[Elbee]

davegee

Quite clever, Dave.

Nicely done.

Best, LB

[davegee]

davegee

Quite clever, Dave.

Nicely done.

Best, LB

Thanks. That was a lot of work trying to figure out aluminum tube segment lengths, telescoping struts as the gear rretracted and extended, etc. The drag strut which is shaped like a Vee, still has to be figured out as the gear moves up and down. I am hopeful I can get a solution on this. If not, I will make the V strut to be held on with magnets for photos and ground observations. It is fairly to scale with the real thing, with the exception of the totally non-scale circular springs on the main struts.But you can't have everything.

Cheers

davegee

[jetfool]

Perseverance has paid off Dave. Excellent! Usually takes me many tries before I get something right. Rex

[davegee]

Thanks, Rex. I think it definitely looks better with at least this scale extension/retraction assembly in place, over just the stock HK gear arrangement. It will do for now. I’m going to make a scale drag brace that I’ll attach with magnets for now. That should look better for photos on the ground. I don’t think the geometry lines up for this model to have them functional in the air. Still, I think my efforts yesterday and today were worth it.

cheers

davegee

[davegee]

I made up a couple of drag braces for the main landing gear and they attach with magnets. From the way the model is designed and put together, I couldn't make them functional so they are there just for appearance' sake on the ground and for photos. The main retract and extension jackscrews I made work ok, but they still need to be fortified a bit as sometimes one of the tubes comes loose at the end of an extension. But I think I can get them working so that doesn't happen, it will just take a bit more work.

I still have things like Callie's propeller decal transfers coming, and a replacement #1 engine cowling for the one that got damaged during a runup with the larger, non scale props that came with the kit when one of the propeller blades broke off and hit the cowling. The newer, smaller, stronger, more scale MAS props I think will work much better than the kit-supplied ones, I think.

Once our winds die down in a day or so I can resume my outdoor testing of the plane before doing a maiden sometime in the future.

Cheers

Davegee

[davegee]

I did a lot more testing on my landing gear detail mods today. For the mostpart, they worked beautifully, but on occasion, something was binding in one or the other, enough to where the gear would not extend. That is definitely a NO GO! So, I removed my detail parts and will think about going about it a little different way that will be workable 100% of the time. I still plan to come up with a scale addition like I've been working on, but it just can't be something that might interfere on occasion with the proper operation of the gear. One time is too much!

I think it is possible to come up with a better design, but in the meantime while I'm doing that, I'll be prepping the airplane for an eventual maiden, weather permitting, of course. I'd like to do it before the end of the year if things come together. Most everything is done, CG spot on after putting about 3.5 oz of lead weight in the nose (due to retractable tail gear, gunner figure in the tail, etc), still have taxi tests to do, but I've got good results on most all other things that need to be checked perfect before putting her in the air.

Cheers

davegee