rideon67

My Feedback: (1)

After being at Joe Nall today, I have pulled this plane from storage and am anxious to fly it. It was built approx 15 yrs ago pretty much to plans (except for the big motor and HD servos) but never flown. The first thing that jumped out was how HEAVY it is with this motor. A huge nicad pack (over a pound) is clear back in the tail just to bring CG close with this setup. Also, back then the heavy duty servos available were world engines S31 and there are three of them adding another pound at least. Did I say this thing is HEAVY? I'd guess at least 5 lbs overweight.

The motor is mounted on rubber isolation mounts that a couple of us engineers came up with (this is before isolation mounts) because of the way it shakes. It was run up on the ground a couple of times back when new and it shakes like a top fuel dragster). The iso mounts are right on the fire wall to keep the motor as far back as possible for CG. I had a spring starter put on the motor because it's a real bear to start and the spring is so strong it feels like the fuselage is goint to twist in half when winding it up. I'd guess the spring alone weighs over a pound.

After looking at todays technology it is obvious that this plane is seriously out dated, but if it will fly I will fly it. Do I need to pull this motor off, change to much lighter servos and battery, and generally bring it into this generation (lose the vibration mounts), or do you guys think I should try it the way it sets? It's gonna be shaking 15 year old epoxy and foam and at this weight probably flying somewhere near mach II. Obviously I could throw money at it and improve the wing loading, but I wonder if this would be well spent and result in a great flyer or still a marginal one that looks good.

Any advice will be greatly appreciated.

Tired Old Man

My Feedback: (1)

For comparison purposes, the 1/3 Christen Eagle from Great Planes is the same as your Byron. In both cases, the lighter your can have it, the better it will fly. Going with a smaller engine, smaller battery pack, and more modern servos that are lighter that what we had 15 years ago will be a large step in a better performing aircraft. Unfortunately, the Byron was never known to be a lightweight.

mglavin

My Feedback: (31)

Does the engine have electronic ignition or a magneto/flywheel?

Loose the dated radio gear and replace with new stuff.

The battery is likely BAD, in any case today’s offerings are going to be lighter.

You didn't mention how it weighed did you? Strip the model and weigh it to see where you’re at, you can then extrapolate completed weight with new component and see if it makes sense.

rideon67

My Feedback: (1)

The engine is an old time orange case Sachs Dolmar with magneto ignition. I understand this ignition adds to the weight and starting difficulty, but don't know how much weight it adds. I sent it to a guy in Texas all those years ago for addition of a shaft extension which is a 6 bolt aluminum. I pulled the engine and it is a MAJOR contributer to the weight. I remember that it swung a 22 6/10 prop so hard it pulled my whole work bench, but I'm concerned this weight will pull off the wings.

Weight was approx 20 lbs with the components in place -- as I remember, the Texas engine guy flew these Byron /Sachs planes and they came in at approx 19 to 20 lbs back in the day, but 20 lbs is sure heavy by todays standard.

I was looking at the DA50 at Joe Nall today, and that would be perfect for this BUT $700 is WAY too much to put into this plane it seems to me.

What servos would you recommend? The ones in there are so old they have 3 prong Futaba AM connectors.

GreaTOne_65

I would like to tell you about my experience with Byron Originals Pitts. I know there are differences but not a whole lot. I powered my Pitts with a Quadra 42 that was more than adequate for the plane but did not over power it. The plans that came with the Byron planes suggested standard servos, in the S148 series.

I actually owned 2 of them, the first suffered aileron flutter and was destroyed. The second one I reallized why the first one was lost, the connector between the top set of ailerons, was to be connected forward of the aileron, a slot was constructed for that purpose, the connector was built with a hollow airfoil shaped alumiunm tube filled with lead that weighed at least 2 ozs. If you read the posts on the Great Planes Christian Eagle you should gain some insight what an over weight Eagle is going to fly like.

Good luck,

Bigger always flys better.

Dale

mglavin

My Feedback: (31)

I'd suggest having the engine retro-fitted with an electronic ignition. This will make a big difference in handling and performance and you'll see less vibration as well. I’d guess you could shave nearly two pounds here. You might even loose the isolation rubber mount these devices are simply not needed.

I'd suggest above average servos, something like Hitec's HS-645MG @ 100in-ozs or so. These are metal gear servos and may not be required of this model but their reasonably priced. There are many other brands that offer similar torque values as well.

I like 6.0V batteries too.

peter1b1

I have just rebuilt a Byron Pitts with a Super Gemini 240 Twin and it weights in just under 9kgs (approx 19 lbs). It flys well although definitely not 3 D. I have had it certified for everything except snaps and unlimited as I was not confident the airframe could take it G loads. Landings like a dream not bad bouncing tendancies, just take off are interesting, have to be very careful with the throttle rudder mix!

I have changed the servo install slightly with two JR 8234 digital servos for the elevator halves and one for the rudder, all mounted at the rear of the plane and two GWS S15 coreless servos for the ailerons. Balances just fine, I have also fitted a slimline smoke muffler and hope to fit the smoke system in the next couple of weeks, looking forward to the "smoke show"!

peter1b1

Couple of photos of the Pitts..

rideon67

My Feedback: (1)

Nice looking Pitts. How much of that 19lbs is the engine and how much power does it produce? I don't blame you for questioning the strength.......I'm a mechanical engineer and it makes me shudder to think of this thing snaprolling at 19lbs. Those center wing supports look like the ones on mine -- milk colored nylon. Is that what your using? I have nightmares of them jerking out of the top of the fuselage.

I had a Byron Cap21 back in their day & the guy who tuned my quadra had a Byron Pitts with Q35 ported/polished/etc. He would snap it both inside and outside, but I doubt it weighed 19 lbs with that little quadra.

What is your rudder throw and what is the throttle/rudder mix you're using?

rideon67

My Feedback: (1)

Retrofit to electronic ignition sounds like excellent advice since this engine is very low hours (I'd guess less than 3). I recall coming across somebody selling the Sachs/electronic ignition on a website under a different name. Do you know anyone who would do the retrofit for me?

The engine/steel muffler/spring starter weighs over 7 lbs and the battery/3 huge servos adds another. Also the aluminum motor mount parts and isolators bring the total up near 9 lbs. I'm guessing by losing the flywheel and spring, changing to aluminum muffler (if available), and updating servos/battery is should come in around 15 -16 lbs. Does that sound like something that will fly reasonably well? (wing area approx 1500 sq in) Considering the profiles I fly come in around 5 lbs for 750 sq in, the Eagle doesn't sound like a candidate for 3D>

mglavin

My Feedback: (31)

Try this guy, he's forgot more than most know. Ralph can do all the work for you and then some.

Ralph Cunningham of RC Ignitions

[email protected]


http://rcignitions.com/

peter1b1

The Pitts is all original and I think it was flown originally with a Quadra judging by the firewall. I have modified the firewall by making a stand off for the OS engine (the firewall is 3mm (1/8") ply!!) my standoff is 5 mm (1/4") and epoxy and screwed to the firewall and the attachment point for the control horns are 1/2" square block epoxied into the foam (originally just bolted through!) The centre attachments are just white plastic epoxied into the fuselage. They show no signs of movement and I check it after every flight! The engine weights in at around 2-3 lbs (1-1.5kgs) I think and produces around 4 hp. It swings a 20x10 Metz prop no problems and the aircraft flys with authority. At this time I have not mixed the throttle and rudder but I am giving it some serious thought.
With the age of the aircraft (similar to yours) around 15+ years old I removed and replaced all the hinges and control horns as I have had a bad experience with a similar aged heli that had a control horn fail under load and trashed the heli, on inspection I found all the plastic was brittle with age so I now just replace them all.

peter1b1

I have a couple of photos of the firwall mod.

peter1b1

I hate that!!![:@] Lost the photos in the ethernet! One more try plus a photo of the aircraft as it was when first brought.

peter1b1

Just found a site with details of the 240 twin,
Specs:

Displacement: 19.96 c.c x 2 (1.218 cu.in x 2)
Bore: 30.4 mm (1.197 in.)
Stroke: 27.5 mm (1.083 in.)
Practicle RPM: 1,800 - 10,000
Weight: 1,880g (66.3 oz) (without motor mount)

Suggested prop range: Scale 20x8, 20x10
Sport 18x10, 18x12, 20x10

rideon67

My Feedback: (1)

Looks like the 240 is a much better power to weight choice for this plane. The Sachs turns a 22-10 but weighs nearly three times as much. The twin will also give a lot less vibration I would Imagine. Is this a doubled up 120 four stroke glow engine? I love my Saito 120 on the Goldberg Ultimate.

Are your aileron connectors carbon rod? I'm definately gonna not use the stock ones after all the bad experiences. The firewall box looks good, but with this HEAVY engine it needs to be right on the firewall to keep the CG reasonable.

Found a place in Charlotte (near here) called Air Hobbies that sells and works on Sachs, so will make a trip there to see what's what for this motor. Sounds like getting a lot weight out of it is not in the cards, but every little bit helps.

Antique

My Feedback: (4)

I had the first Byron Pitts in Phoenix, and later a Christen Eagle...The Pitts was designed many years ago for a .61 engine with a tuned pipe and if built to the plans, covered with Econocote, would weigh about 14 lbs...The fuselage is only foam with a thin firewall...If any gasoline gets to the fuselage it will melt..My Pitts had a Rossi .61 with a pipe and the Byron belt drive, turning a Zinger 20-8 about 7000 rpm...flew OK, but not great...I later put a Q50 in it and improved it a lot..My Eagle was powered at different times by a Tartan twin, a 240 Enya V twin, and a Saito 270...Best performance was with the Enya 240.....
A Byron Pitts built to the plans and covered with Econocote is not strong enough for a big heavy gasser....It will work for a while, but don't expect long life...A friend built one and fiberglassed it...It was gorgeous but weighed about 23 lbs and didn't fly well at all, I had adapted a ST90 to the Byron belt drive..
The aileron flutter problem was cured by counterbalancing the ailerons with lead weights in cutouts in the wing, built according to the plans....

peter1b1

The 240 is not a doubled up 120, lots of differences and you can't get them now, there is a chap running a 300 twin in the GP Pitts it basically a bored out 240 with a lot more grunt. The original engine mount was just a small wooden block angle to give the required right thrust and to keep the engine as close as possible to the fire wall. With the 240 as I said before I put the servos in the tail to help out the C of G. Very little vibration from the 240 and it sounds fantastic. I am using the stock connectors for the ailerons and to date no problems.

PlaneKrazee

My Feedback: (14)

RCIGN1,

Would you still recommend the Enya 240? I have a 240 that I just ran-in this summer. 9000 rpm on Byron 5% nitro and a Mejzlik 20X6!

Did you mount it inverted? How did you start your 240? I hate to eat the spinner with a starter.

My other options are a BME 50 or a OS 160FX.

cfv007

My Feedback: (5)

How would a OS BGX work or maybe a Saito 2.20? I ask because I just acquired a complete Pitts kit. I have these two motors as well as a couple old quadras (a 35 and a 50) I also have a Sachs 3.7 too.
Chuck

CK1

My Feedback: (60)

I have been flying the Byron CEII 's for several years now on gas and I can tell you that they fly well if kept near or under 17 # AUW .
Gas is a problem with foam, it will desolve it quickly . Make sure your plumbing is perfect.
You do need to double up on the firewall and reinforce it with more glass , the stock firewall is not thick enough in my opinion ,even if flying glow power.
I strongly advise trashing the oem Aileron setup and opt for indidual servos on the lower wing driving the uppers with the stock rods (this saves wieght over using
4 individual servos but is much better than the sloppy torque rod setup.
Cover with econokote , glass isnt necessary and its heavy.
Be very sure that your wing spars are well bonded to the wings ,This is the week point on all Byron CE and Pitts
The wings will fold on a high G pull out if the spars dont hold .
I currently am flying 2 on gas , a 3W60k and a D&B 3.7 twin.
They fly very well at 17 - 18 pounds and land well also , if you get above 18 -20 pounds recovering from stall maneuvers is slow and sluggish and
landing is an event in itself.
My AUW on the 3w60k is around 17 # and the D&B is around 17.5 #
These are not 3D aircraft but they can snap and tumble and perform perfect inverted flat spins that are really hard to recover from . I love 'em

PlaneKrazee

My Feedback: (14)

Do you recommend white (Elmers) glue or 30 minute epoxy for the wing spars?

JohnnyJ

My Feedback: (1)

Hello,
I had(my friend is flying it now with a G62 in it) a Byron Christen Eagle that flew well at 21lbs with a G45 on CH ign on it.
The vertical wasn't great and it wasn't a floater. I did have fun with it and it looks good in the air.
Not that hard to land 3-point either!
I modified the muffler similar to the one in the photo and the G45 turns a Bolly 22x10 at 7100 rpm.
Go fly your Eagle and have some fun!
Good Luck!
John

Antique

My Feedback: (4)

My Enya 240 V twin flew the Christen Eagle a little better than the Saito 270 and was very easy to start, just like any glow engine that size...Bump the prop backwards...Cant remember the prop size, probably a 20-10 Zinger..Vertical was very good, can't remembe the weight of the plane...It was covered with EconoCote...It flew well with the early Tartan twin, but the Enya was the best.....

PlaneKrazee

My Feedback: (14)

RC,

Did you mount the VT 240 inverted?