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oscillator
Jul 06, 2008, 09:45 PM
The warning signs were all there - should have just gone home, but I pressed on.

After struggling to fly my Espada R (took 3 tries to get a decent flight) and ground looping my Yak by landing in a ditch, I decided to fly my Escape.

I hadn't flown the Escape in several months. Putting her together and holding her on the winch line was like saying hello to an old friend. I had forgotten how much I liked this plane - she last flew at the Fresno classic. While at the contest I assembled the Espada R, maidened her after the contest, and hadn't flown the Escape since.

I had removed the bar graph volt meter from the Escape some time back and installed a Spektrum data link (displays digital voltage). This would prove fatal. As part of the preflight I checked the voltage - 5.2V. Humm....was this a 4 cell or a 5 cell setup?....a quick peak and I convinced myself that it was a 4 cell (it wasn't).

Well, you can guess the rest from here....launch was beautiful, flew like a dream for a few min, and then....well....she started behaving erratic. At first I thought I had hit some real big air. By the time I realized that was not the case, it was too late (prob couldn't have got her down at that point anyway). At one point she did a huge outside loop - while I was holding full aft stick! There are these little moments of denial - "Oh, maybe I just lost orientation and dumb thumbed it." No stupid, you are just a spectator. Turn off the transmitter and go home. Thank you for playing. :mad: :( :censored:

She went straight in from several hundred feet and impacted pavement. Thank god no people or property were hit. The nose was completely gone. I found the RX and servos back in the tail! :eek: Wings skins are all mushy, but the spar is amazingly still solid. Tail boom is fine, but the tail feathers sheared off.

Basically it is a write off. Servos and RX are fine. Battery is gone. Airframe is gone. I know most people have a story or two like this one, so it was bound to happen sooner or later - but it just irks me to loose such a nice plane to such a stupid mistake.

-Mark

schrederman
Jul 06, 2008, 09:55 PM
Sorry, Mark... I hate to hear it.

Twizter68
Jul 06, 2008, 10:04 PM
That sucks, Mark. I lost a Spirit 100 RES after a beautiful launch...when the retrieve line got wrapped around the vert stab and snapped it off. It was all I could do to keep it off the road after that, took it home in a trash bag.

equest
Jul 06, 2008, 10:31 PM
Damn Mark..........Loosing any Espada is just shear agony. Sorry to hear it happened to you.

Equest

jtlsf5
Jul 06, 2008, 10:48 PM
Its not clear from you description if this was a 72 Mhz ship or 2.4. If it was a 72, and it had a crystal, toss the crystal. It may have survived but most likely it is fractured or the interconnect between crystal and pins is intermittent. Don't compound one goof with another to save a $8.00 part.

Sorry you lost the Escape. Always cycle the batteries in a ship that hasn't flown in a while, and cycle regularly during the off months. If a pack gets below 90% of rated capacity, toss it. I've been fortunate never to have lost a plane to bad batteries in 28 years with this discipline.

JT

oscillator
Jul 06, 2008, 11:30 PM
JT,

I couldn't agree more on the cycling. I will be much more rigorous in my battery care from now on. Hopefully this will be a reminder to others and maybe save a few ships.

The ship in question was 2.4. I must admit I am somewhat leery of the RX now - after taking such an impact....

Equest - the Espada is fine, it was the Escape that died. Still bad, but the Espada would have been worse.

-Mark

oscillator
Jul 07, 2008, 01:04 AM
Update:

My 921 RX appears to be dead. Using a fresh battery, The lights come on, but I can't make a servo move. I tried re-binding - all the lights blink and go solid just like normal, but no movement on any channel. I even tried a brand new servo with none of the old servos connected - no joy. At this point I'm reluctant to trust anything removed from this ship - looks like a total write off.

Kai@UCSB
Jul 07, 2008, 01:13 AM
Mark,

Sorry to hear about this.
Where did you crash? Bayland?

-Kai

lincoln
Jul 07, 2008, 01:21 AM
It does hurt, doesn't it? I recently had a flyaway and a coupld of nasty crashes. Short circuit between ears. If you went through this and didn't throw some sort of tantrum, pat yourself on the back. (While I didn't exactly throw a tantrum, I was not good company for a while.)

If you can put a load on the cells and wait a few seconds, then even if you don't know if it's 4 or 5 you may catch a dead pack anyway.

Hostage-46
Jul 07, 2008, 01:27 AM
Boy that one is tough, I remember my first real crash of a proper sailplane. My Compulsion, something was not right on the pre-flight, just a little off, couldn't put my finger on it.... ah hell with it, I'll just launch and feel 'er out.

Up she went, and then died at the top ... augered in at the speed of heat, the first time I ever took the wife to the field ... at least she felt sorry for me :(

Sorry for your loss man... and any parts inside that ship are clearly jinxed ...

OVSS Boss
Jul 07, 2008, 07:28 AM
They all have an expiration date don't they.

Marc

tewatson
Jul 07, 2008, 09:02 PM
That sucks. One thing I did a while back to prevent any confusion on batteries, was to standardize on a single pack style for all my TD and F3B planes...(five-cell, 1,500 MAh flat pack). That way, there's no trying to memorize what pack size/cell count is in a given ship. Charger settings and check routines are the same for all.

Tom

seanpcola
Jul 07, 2008, 10:02 PM
I turned into a real battery :censored: a couple of years ago after someone (who will remain nameless here) piled in a very expensive scale job for the same reason. I now have labels everywhere, Mah, date of purchase, cell count, on and on. I am now known as the battery wimp (or worse). I have a pile of high end chargers, battery analyzer on my PC, on and on. And even after that I went with a rule that I pull packs after one year on anything I care about and replace.

Sean (Having said that will lose one next weekend due to an unrelated glitch :rolleyes: )

jtlsf5
Jul 07, 2008, 10:11 PM
Tom and Sean bring up great points. There is a very basic and key theme in what they do and what I do. Be systematic. That means devise a system that works for you and stick to it, come hell or high water.

I document and test. Tom standardizes on one size fits (almost) all; I know you don't use the same 5 cells in your HLs. ;) Sean documents and tests.

Bottom line is your $500-2000 plane is completely dependent on that ~$25 battery pack. Nothing is more critical in the link between you and the plane. Take care of it and your planes will always survive to fly another day (barring the pilot doing something really dumb).

JT

seanpcola
Jul 07, 2008, 10:24 PM
Tom and Sean bring up great points. There is a very basic and key theme in what they do and what I do. Be systematic. That means devise a system that works for you and stick to it, come hell or high water.

I document and test. Tom standardizes on one size fits (almost) all; I know you don't use the same 5 cells in your HLs. ;) Sean documents and tests.

Bottom line is your $500-2000 plane is completely dependent on that ~$25 battery pack. Nothing is more critical in the link between you and the plane. Take care of it and your planes will always survive to fly another day (barring the pilot doing something really dumb).

JT

Yep, I got it all covered. ;)

Except that "dumb" part. :o