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        Question How Safe Is A 20 Year Old Aircraft

#1 Rickochet Feb 02, 2013 07:25 AM

How Safe Is A 20 Year Old Aircraft
 
I have a 20 year old Eagle II I have had stored in my basement that I flew with a Royal .46 back in the early 90's. The motor and tank are gone but the servos are still installed. I had thought about converting it to electric.

My biggest concern is the 20 year old glue joints. It was done primarily with CA and I used the wicking type CA hinges. This plane will weigh about 5 lbs. and I am concerned about it coming apart in mid air and maybe hurting someone.

Any comments would be appreciated.

#2 lrb75 Feb 02, 2013 08:04 AM

The pots in the servos might be a little dirty too. They may clean up after a few cycles or they may jitter. Balsa gets more brittle and the covering will be brittle. If the covering holds up to pushing on it some go fly it. The wood won't really be any weaker for flying it will just tend to shatter in a crash.

#3 ChrisS Feb 04, 2013 05:02 PM

Interesting question, ask it of any of the large carriers, Delta, Jetblue, USAir etc.

If you can't find issue on the bench, it should do fine in the air. Treat it like a new, unflown airframe. Twist it and try to stress things without breaking them. Shouldn't be hard to tell at all.

I'd replace all the electronics just 'cause. Servos are cheep and radio gear has come a long way in 20 years.

Chris

#4 reno4sure Feb 06, 2013 08:13 PM

I recently converted a GP P-51 from nitro to electric that my dad flew many years ago. It has to be over 20-25 years old. You can still smell the nitro in the plane! Other than a few patches here and there, the plastic wheel wells etc, (the plastic was brittle) this thing fly's super. I constantly say I'm going to retire it, but it flys so well. The guys at the field can't believe it is still flying.
Reno

#5 Evan D Feb 07, 2013 09:23 AM

I have a VK Fokker Tri-Plane I built in 1979 that I flew on and off through about 1990. Last year I pulled it out and converted it to electric. The structure was fine but I did't trust one of the servos and replaced it. I didn't like how I originally built the rudder drive train, a push rod to a plastic servo wheel made to act as a belcrank and then push pull to the rudder. I re did that...

#6 Rickochet Feb 07, 2013 11:03 AM

Thanks for all of the replies. I think I will replace the servos and give it a go. I bought the motor for it years ago but it just kept getting bumped down in the build queue. I recently downloaded a Sig Senorita on Real Flight and forgot how nice this size aircraft flew. I am concerned about the CA hinges and may add some Blenderm tape just to make sure about the control surfaces. I also need to figure out a place access a battery box since I don't want to have to remove the wing every time I change a batt pack.

Does anyone have any suggestions on servo size? Also would metal gear ones be suggested?

Thanks again,

Rick

#7 taildragger1589 Feb 07, 2013 06:37 PM

Hi guy!

My son is using the Hitech blue 9gram servo in his four pound, sixty inch span J3 (it's fast) and has been working ok for a few years. Probably has about the same servo loads your ship would see.

I'm electrifying an old Geebee Dreamer, a forty powered four and a half pound biplane that's very hot. and I'll be using Hitech H-81s in it. They have a good bit more torque and seem to have a smoother gear train too.

I can recommend both depending on whether you want low cost or pay a little more for a little insurance.

Nick:)

#8 Ldm Feb 08, 2013 04:14 AM

great question , but weather its 20 years old or 1month , the relevance of checking everything is the same .
My assembly of arfs or build threads are boring and long and typically twice as long as the avg member on rc groups .
Why ?
Well I have my own anal process of testing servos, connections , flex in control rods , sealing flying surfaces , checking control horns , reinforcing horns that are cheap , glassing firewalls , retract bays , reinforcing weak points in sheeting ect .
If my planes crash its 100% pilot error and not faulty plane parts .
So check everything critical to safety and prone to break and you should be fine

#9 CNY_Dave Feb 15, 2013 11:23 AM

I flew a '90s vintage ARF trainer until my DX5e killed it.
No glue joint failed in any of the pilot-induced crashes I had.

I have flown the heck out of a slightly newer than that Fokker ARF, and only the glue joints that were done poorly by the previous owner have failed under, um, trying circumstances.

I have 3 1970s vintage planes (not ARFs but assembled back then) I will be flying at some point, one is just about ready to go.

#10 dedStik Feb 15, 2013 11:42 AM

I had a Great Planes Trainer .40 that had been in storage for 20+ years as well. I finally dug it out intending to restore it and convert it to electric.

I removed all the covering all control surfaces to check the integrity of the airframe and to address any repairs that needed to be done. I then replaced all nylon in the plane from hinges, to linkages and control horns, I removed the original push rods and installed updated laser rods.

I did my motor mod and installed the electronics replaced all servos due to the 20 year old gear. Once I was happy with the repairs and upgrades I bought a few rolls of monokote and I recovered the plane.

I did this restoration about a year ago and just flew the plane for the first time last month and she flew very well. I've logged about 5 flights on it since then.

Any glow to electric conversion should really depend on 1 main factor, the level of damage done to the wood from glow fuel. I was lucky in mine that the plane originally only saw 4 flights back in the late 80's so it really never made it past the engine breakin period.

Build thread with pics here.

http://www.rcgroups.com/forums/showt...ner+40+convers

#11 DeadTom Feb 15, 2013 01:30 PM

Interesting thread, I have 3 balsa planes that are 30+ years old.

1 is a Sig Kadet Senior with an OS .40, this one my dad built and gave to me when he decided not to fly anymore. All I have done is change out the old 72mhz radio with a Spektrum full range rx and a new battery pack, same old Futaba servos, Flies great.

2 is a low wing plane OS.25 powered plane that I designed a fueselage for when my older brother gave me an old wing with ailerons, he could not remember what it came from. Changed out the old 72mhz rx added a new battery kept the old servos and it flies great still.

3 is a Carl Goldberg Electraflyer (Gentle Lady look-a-like in electric form) that came with a 400 size motor and used 6 "C" nicads batteries, this never flew and was changed to a Cox TD.09 it can be pointed straight up and it gains altitude quickly. Same with this one as with the others changed out the 72mhz rx, new batt and kept the servos.
All three were made with aliphatic glues and Ambroid. I never really thought of glue joint degradation and the monokote getting brittle, something to watch out for.
Good luck

#12 Rickochet Feb 15, 2013 02:17 PM

Quote:

Originally Posted by DeadTom (Post 24145222)
Interesting thread, I have 3 balsa planes that are 30+ years old.

3 is a Carl Goldberg Electraflyer (Gentle Lady look-a-like in electric form) that came with a 400 size motor and used 6 "C" nicads batteries, this never flew and was changed to a Cox TD.09 it can be pointed straight up and it gains altitude quickly. Same with this one as with the others changed out the 72mhz rx, new batt and kept the servos.
All three were made with aliphatic glues and Ambroid. I never really thought of glue joint degradation and the monokote getting brittle, something to watch out for.
Good luck

I forgot that I also still have a Great Planes Spectra electric powered sailplane from the early 90's. It was my first electric and had a can motor and used 6 cell nicads as well. I had thought about upgrading it but have too many other builds in the queue. I used to be able to speck out the 2m Spectra even with the heavy battery pack. Now that my eyes are 20 years older I could probably speck it out at half the altitude. :o

#13 DeadTom Feb 15, 2013 02:44 PM

Yeah my old Electraflyer was too heavy for the thin atmosphere here in Reno and it never flew but once and then it never got higher than 10-12'. I milked it around the flying field above the sagebrush and then accidently cart wheeled it off of my dad's new truck.
At this point I removed all of the heavy electric components and installed the TD .09. This was before brushless motors and lithium batteries.
Yes it is harder to see the planes far away anymore so I try not to go to far out or too high.

#14 taildragger1589 Feb 17, 2013 12:49 PM

Quote:

Originally Posted by Rickochet (Post 24145595)
Now that my eyes are 20 years older I could probably speck it out at half the altitude. :o

My first electric was a self designed 108" V-tail I called "What" (watt) and was powered by an Astro 05 and Lord knows what kind of nicad combo...
It staggered up to about 50' if the air was good and flew for 6 or 7 minutes. Just enough time and altitude to catch a thermal, which didn't happen often.

anyway 37 years later, I don't have to buy full range receivers anymore since my six foot span fliers don't often get more than 200 yards away anymore. ;)

Nick
PS at the time, my other fun flyer was a tarus with a max gold head 60.:D


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