kahloq

Here is what i have ascertained regarding the mains and not operating well.
I took the mains out of the plane and tested them still hooked together. No kinks whatsoever. The operation did not improve. I did each gear alone and they seemed to work fine. I put them back in the plane making sure no kinks. Same operational status as before. They work(pulling the gear up at very high psi). But after dropping to 70 or less, its very hard for the gear to get the struts and wheels up.
I then flipped the plane over and retested. Well, this time, the gear will retract easily into the nacelles and then deploying them is the problem. So, bottom line is, the wheels are pretty heavy for the air cylinders in the retracts and its having problems raising the weight(whether the plane is right side up which would be retracing the gear...or upside down and deploying the gear sicne gravity is assisting the opposite direction of the problem). The only solution I can come up with now to get around this is to simply put an air system for each main thus there would be no split of the air volume or pressure.

Any thoughts on this?

Eldher

Kahloq,

try running your system at 120psi. I run mine at 120psi and everything works very snappy! hopefully should be enough to get you 3 reliable cycles.

eldher13

kahloq

I will try that, but not until I get more of those little metal circular hose clamp things you twist on the air nipple connections. I dont want to blow a line.

Eldher

Here's a video of the third flight. Boy, I like this airplane!

http://www.youtube.com/watch?v=TULzeGhVcQQ

Enjoy!

kahloq

Here's some new photos. One of the bomb drop setup showing the servos etc. They are hooked into a JR matchbox with its own battery feed.
The entire plate will be held to the bottom of the wing with a series of magnets. This will make reloading the bombs very easy as all Ill have to do is reach up and pull the plate out and slap the bombs in and replace the plate.
The others are showing the cowls painted with the mini airscoops/exits. They were made functional.
There's not much else to do to the plane except give the greenhouse area a little interior work.
The only thing keeping me from getting it to the field to do engine tests and taxi and finally a maiden is I have no way to currently transport it. It doesnt fit in my H2 without real serious risk of breaking something on the plane.
But...I am currently building a cargo trailer to haul it

kahloq

Here is are a couple new pics. The pilots are from parkzone. They are the right scale and are much better then nothing. There are much more authentic looking bomber pilots(even pre-painted), but paying up to $100 each is not something I wanted to do.

The cowls(and all smaller cowl pieces) are fitted and fixed in place now. The prop hubs are truturn.

kahloq

Plane is basically done. Just need to check balance. She came out rather heavy at 32 pounds. Now...this is with everything onboard except fuel. This includes the bomb racks, the bombs themselves, etc.
Eldher13's plane takes off at about the 450 ft mark on our 800 ft runway and his weighs about 28 pounds. If RPM's are about the same(we are both usign same props), I hope that the 350ft left over is enough. I am sure it is, but its going to be hair raising to say the least.

ronmustfly

My Feedback: (7)

I just finished my KMP B-25 and required 2 1/2 lbs. in the nose to balance! Does this seem right?
I have 2 O.S. 110a engines in it. Any comments would be appreciated.
Thanks, RON

Eldher

Could be. Mine is flying and I had to add 1 lbs. to the nose. But note that I have 2 Saito 150's mounted, these are heavy engines.
If the 110's are light engines, then, you could end up adding a lot of weight.

F82FAN

My Feedback: (10)

Hi Guys,
I've been away for a while and wasn't receiving the updates. Nice to see the fleet is growing!
Very well done on the maiden, drMikie! You sure made it look great. It didn't seem too hot when you rolled her onto the runway?!

Elder13 - Super great stuff, eh? It is WAY big fun.

kahloq - It's your turn in the barrel... When will we get a flight report??? Hopefully soon.

I've not flown the Dream in a couple of months now, so its time to charge the batts n get back out there!

Take care, all. Hope to hear some updates soon.

Wally

kahloq

A flight report may or may not occur this month. If it hasnt been raining, its been windy on my days off. Also, if something were to get damaged now(on a flight test), there'd be no time to fix it for Warbirds over the Rockies end of this month.

F82FAN

My Feedback: (10)

One last suggestion would be to put a BIG fish scale on the '25 to see which props pull better for your maiden flight.
Yes, it looks good with threes, but if it flies better on 2-blades, you ought to test fly with those!
It's all about the thrust at your ALT.
Good luck!

Eldher

YEH, SUPER is the word. Put 2 more flights on mine last weekend. YEEEHAAA

kahloq

Too windy again today to attempt anything. Seems the weather just doesnt want to cooperate with me.

F82FAN

My Feedback: (10)

Some YEARS are like that.... Hang in there - it is worth it - as you've seen!
Wally

kahloq

Took it to the field a few days ago to run the motors now that they are installed on the plane. Got it all setup at the runway and then attempted to start the motors and nothing.
Seems the onboard glow batteries went flat even though the motors havent been run.
These are hooked up in a way that when the RX is turned on, these glow units automatically detect that and send juice to the plugs up to a certaqin throttle setting. I kept forgetting to move the throttle stick high enough to shut them off when doing other things on the plane requiring the RX be on.
So, me working on the plane doing various things ultimately drained the batts to where they now read absolutely nothing with a voltmeter.

AS a remedy to this, I put in some MPI charge/jack on/off switches on each nacelle and now manually turn these on WHEN I want power to get to the plugs.

Balancing this thing is rather difficult unless you use some form of plum bob technique from a ceiling while the front and back sections of the plane are tied up to twine hanging from some hook.

Since my rafters in the garage are all metal, this wont work for me so had to use Eldher13's modified Great Planes balancer. I have one, but the small pads will push right through the bottom of the wing.

Now for the bad news......Im already at 32 pounds, but now seems I have to add a pound of dead weight to the nose

Also finally got one of the motors running on the plane, but the other one started and then stoped 3 secs later and wouldnt restart.
I pulled the tank out today to check for kinks in the fuel lines and didnt see any. I reinstalled the tank and made sure the orientation of the tank was correct. So, we'll try again here shortly(tonite hopefully)

kahloq

Got both motors running tonite, BUT, seems the twinsync device is trying to play catch up back and forth between the motors.

The one motor from last time that wouldnt start is now fine and got 8000-8100 rpm's on a 16x8x3 MAS prop.

The other motor that ran fine before seems to be getting messed up by the twinsync when the 1st motor is running. Also, the onboard glow device is cutting in and out with no change in throttle on that motor for some strange reason.

kahloq

Not sure what's going on now. Had the plane out to the field to at least try and do taxi tests after getting the motors tuned and synced up and couldnt even get both motors running well at all. The inside cylinders are not lighting when I try to start them UNLESS I remove the glow heat from the other cylinders, start the motor, then manually add back the glow heat wires to the plugs for the other cylinders. Then the motor runs fine unless the RPM's dip low again. Im thinking there's two issues...one is the batteries for the onboard glow just isnt delivering the voltage to the plug wires needed to heat the glow plugs well enough for 3 cylinders and/or the needle settings are just not cooperating.
Since both motors tend to do the same thing(the inboard cylinder has trouble firing), Im betting its the voltage issue and that the those respective cylinders are getting flooded when trying to start so even a little orange glow on the plugs is not enough to overcome that.

Im going to change the glow plugs first and then hook up a 6v battery and see if it makes a difference.

On a sad note.....I witnessed a Zirolli B-25 maiden flight yesterday(8/23) and it appeared to fly ok. It flew scale....not a lot of excess speed, but seemed ok making turns and such. On landing, the pilot used the steep dive to the runway type of approach. The pilot is a skilled pilot that does fly jets, but, the B-25 was not HIS plane. He was flying it for another member that spent 2 years building it.
Anyhow, he comes in rather steep and starts dropping the throttle(he said he went from 3/4 throttle to 1/4) and the plane simply fell out of the air. He tried to correct it with elevator, but simply didnt have enough throw to compensate for that steep of an approach. It didnt spin in, it just went from about 20 feet high flying to ground level in about one second. The plane was short of the runway, so when the gear touched the ground, the plane basically shattered on one entire side. The left wing completely blew apart.
It was 101" wingspan weighing about 44 pounds and was powered by fuji 36 cc size gas 2 strokes spinning something like 17x10 props. The pilot said it was very marginal on power and was at full throttle the entire flight.

F82FAN

My Feedback: (10)

Hey K,

Sorry to hear about your engine issues. If I knew anything about them I would offer some suggestions, but I don't even have any friends that have ever used one - much less TWO on twin-sync!
Oh, the troubles we bring forth on ourselves in this great hobby......

Really sad to hear about the splattering of a Ziroli -25. I always hate to hear about things like that. Guys put their heart and souls into those projects and it can all be over, like that.

As you've seen with our fellow 25'er elder13, just fly it all the way to the runway and you won't have issues!

Keep us posted on what you find about the engines.

Rip n Bank

Kahloq,

My money would be on the glow battery voltage as the culprit (or alternatively, the gauge and length of the wiring between the glow system and the plug).

Let us know how the test with a 6 volt battery goes. I'll bet it gets all three glow plugs hot enough to get all three cylinders running reliably, or at least running long enough to actually begin tuning it, which will also help!

Man, did I groan reading about the Ziroli B-25 incident. I bet both pilot and owner feel like CR**.

I'm not a big fan of flying other people's planes. While I've taken over a Tx thrust into my hands by a friend I was spotting for when he got dizzy during a WOtR flight, I typically never want fly anyone's plane, and would definitely not do so with one that was two years in the building, or on its maiden flight, much less both!

One, I'd hate to crash it because of my mistake, but just as important, I wouldn't want to be "set up" for crashing it because of the owner's mistake (eg: underpowered, tail-heavy, insufficient elevator throw, bad engine tuning resulting in engine out in flight on a twin, low Rx battery voltage, etc.). The first is relatively within your control, the latter isn't.

I believe one should maiden their own planes. I mean, the owner is probably going to fly it on the "2 thru nth" flights, anyway, right, assuming the plane isn't two levels above their skill set. And if my plane is destined to go down on the maiden, I'd rather have had that few minutes on the stick flying it than not having flown that plane at all!

That said, I would want that experienced flyer standing next to me (and spotting) for my maiden, be familiar with my Tx ("give me right trim"...."I'm deadstick, don't know if I can make the runway; hit the gear switch when I say to" , etc.) and just do the flight myself.

Rip

Eldher

Had a hard landing and broke my WING!

F82FAN you WARNED us that the center section is weak, an boy I just found out. OUCH [:@]

For all interested, here's photos of the repair. I'll be doing the same treatment to the other wing after the Warbirds events over the next 2 weeks.

Flyright

My Feedback: (92)

Sorry to hear of the damage on your "25" eldher13.

I placed a couple of doublers on the existing ribs in F82fan's wing along with additional spars between the existing spar and TE. after they were installed I added 45 degree balsa ribs to limit the twist in the center section. The existing "hardwood" is brittle and breaks easily. The wing is rock solid after the fix, even with a few more less than perfect landings. F82's "Betty" is still going strong although the nose gear has been wiped out a couple of times due to "depth perception" problems with the edge of the runway! [sm=lol.gif][sm=lol.gif][sm=lol.gif]

pitsspecial

Hi Guys,

My friend has just purchased a 'YT' B25 which is the same as your 'KMP' one, he says there is nothing in the instructions about what strength servos to use? what have you guys used? he is a Futaba radio man, so would say 3001's be ok or does it need heavy duty servos in it?

What i have seen of it, it looks a very nice aircraft, i will try to get him to sign up to RCU then he can join in with this thread.

Thanks guys,

Di n Dave....

Rip n Bank

My advise to your friend is to use EXCELLENT quality servo's in this ~$2500 aircraft! This is not the place to start trying to save money!

I use Futaba, also, but I wouldn't put 3001's in a 40-size warbird!

Eldher13 and I decided on HiTec HS635HBs for ailerons, HS5625MG (digital) for elevator (probably the most important servo on the plane), and HS475HBs for flaps and nose steering. My throttle servos ended up being 635HBs, which may be different from Elder13. Rudders are the mini HS225MGs.

Cheap? Nope! Effective and reliable: probably, and certainly a far better investment in this plane than 3001's...

Rip

pitsspecial

Thats great!!!

That is why i love using RCUniverse!! i know im going to get a sensible answer from the members!! SUPERB!!

I totaly agree, this for my mate is a very large project, and after spending so much on the kit, retracts and engines then to put inadequate servos in would be daft! thank you for listing the Hitec servos, again lots of guys over here in the U.K. use them with great results, i dont think they are expensive, i try to use 'coreless' servos because i find them very smooth, digitals can be expensive but they have so much stength and holding power, i would hate for this to come to the same end as the Ziroli B25 in an earlier post, he must of been gutted....

Thanks again for your help,

I will let you know how he is getting on as he progresses,

All the best,
Di n Dave...