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  #11  
Old 05-04-2009, 10:59 AM
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BEC BEC is offline
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Quote:
Originally Posted by shrox
It's not that bad, but until they stop underpowering the electric models, it won't be equivalent.


I can't let this go.... I may be a BAR and still coming (back) up to speed but I've been in electric powered R/C airplanes continuously since the mid 1970s and exclusively (no oily, noisy airplanes) since about 1982.

Once upon a time (when the best energy source was Sanyo NiCds) one had to choose between "underpowered" and duration - you couldn't have both lots of power and flight times similar to what the average glow guy flies (about 8 minutes).

Now it's easy to have unlimited vertical and 15 minute flights in the same airplane thanks, primarily, to the use of lithium chemistry batteries - mostly lithium polymer - as the energy source. Some will argue that brushless motors are part of this revolution as well, but a good old Astro Flight cobalt brushed motor is more efficient than any of the inexpensive far-eastern brushless motors. One has to buy Astro Flight brushless or a European (or higher quality eastern motor such as Hyperion or Scorpion) motor to do better.

Granted, it still takes big bucks to fly big airplanes electrically with as much performance as you can with a noisemaker, but it's all off the shelf and out there now.

Being "green" has nothing (or little) do to with it for me. It's about reliability, and quiet, and, until the lithium revolution, the challenge to get good performance. Maybe that's why I'm back to rockets now - challenges again.

My only comment on turbines is that they're cool to watch - I'd never own one. As for being treated differently by the AMA - they have a much higher potential for creating a literal "smoking hole" than other types and at least until very recently (with kerosene start, better ECUs and software) required MUCH more care to operate safely.
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  #12  
Old 05-04-2009, 11:00 AM
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ghrocketman ghrocketman is offline
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Most of those older electrics with Astro Cobalt Motors were not underpowered but they weighed a TON due to all the cells. A typical Astro 40 powered plane usually weighed about 2-2.5 POUNDS more than a typical glow 40-powered airplane with 24 cells. If you like high-thrust low-speed flying, electrics may be okay, but 6,600 RPM is NOT going to fly any aircraft at what I'd call a reasonable speed unless you are using about 15" of pitch. My piped OS 40FSR's and 46VF's would turn a APC 10x6 prop about 14,000 RPM. My Rossi and Nelson 40's FAR exceed that RPM. THAT's a REAL flying RPM in my book. 6,600 is a high IDLE !

Music to my ears is an UN-muffled nitro-piped Cox Conquest .15 pylon engine running 40+%nitro fuel with a 6.5x6.5 prop at about 24,000 static RPM that unloads to about 30,000 RPM in the air. The 1/4 midget pylon planes I flew those in would lap those in the pattern at the R/C club about 3-4 times before they would circle the field ONCE. One of my favorite maneuvers would be the high-speed diving "Split S" that would end in a 5' high 180mph pass over the runway. Some of the club members loved those, some hated them, but they were always fun.
One guy that crashed more often than he successfully landed actually had the stones to complain to me about the safety of doing that. At the time, I was the V.P. and founding member of the Holly Cloud Hoppers R/C club and this guy had joined the club 1 year ago. The club safety officer heard this guy and very politely told this bozo that I spent probably 10 times more hours giving R/C INSTRUCTION to new pilots than he had in total airtime. He also suggested that this guy would be better served in becoming someone who could actually keep his own aircraft in the air and let the safety policing be his job while he mentioned that I was probably the last person he wanted to tick off in the club.
After that conversation I told the guy to get the hell out of my face before I go over and kick the snot out of your already mangled airplanes. The guy actually never flew at the club again, but stopped by several times.

Glow engines are very EASY to start once one gets the PROPER technique down. Use an electric STARTER (external or onboard) to start your airplane ENGINE, not for power.

As far as the noise, I fortunately don't have to worry about it as my neighbors find the sound of 2-stroke dirtbikes to be pleasant, not annoying. Even if they did care, I would NOT. Never have really gave a rat's ^$$ about the opinions of my neighbors anyway.

As if nobody knew this already, I'm about as ready to embrace the idiotic "green revolution" as I am to believe the Moon is made of GREEN CHEESE. I'm about as green as a petrochemical company was in the 1950's and I LIKE IT !!!!
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  #13  
Old 05-04-2009, 12:16 PM
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shrox shrox is offline
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I was mainly referring to off the shelf planes sold at WalMart and the like, they are the modern day equivalent to planes like the Cox PT-19 control line trainer, or the Stuka. Those were not underpowered like the starter electrics are now, not a great introduction to the hobby of flying model planes. I realize the control line and RC are very different, but as a kid both were cool, just that RC was way inaccessible to most kids then.
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  #14  
Old 05-04-2009, 12:24 PM
Rocket Doctor Rocket Doctor is offline
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Several years ago, Estes, started getting into "ducted" electirc motors, they are very powerfull. They use these on their large, high end planes.

I always liked the "drone" from those gas powered motors, like a giant bumblebee, a really great sound, like the "woosh" of a rocket taking off , the the smell of black powder, can it get any better than that?

Has anyone flown a large RC Helicopter?
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  #15  
Old 05-04-2009, 01:05 PM
bob jablonski bob jablonski is offline
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I still got some C/L planes (some with Cox power) the only option near that would be the Norvel which I think is made in the old USSR. (I still like the Black Widow)
Mr. Bob
Starlight dude
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  #16  
Old 05-04-2009, 01:37 PM
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BEC BEC is offline
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Agreed that the RTF stuff in WalMart is a poor substitute for a Cox PT-19 (at least near sea level). The Stuka or the P-40 (which was my first one) were not good first planes, but that didn't deter us trying.

The situation these with introductory airplanes at mass marketers is not that far from introductory rockets (save for Estes engines) at mass marketers and as Chinese toy makers get more deeply involved I think it is getting worse.

I doubt we'll see an introductory RC (or maybe control line again) airplane at Wal Mart or Target that's as good a value as a Cox PT-19 was when we were kids....(or at least when I was). It could be done, but not for $40. There are some available in hobby shops (stuff that Horizon Hobbies, in particular, has developed) that are good intros at between $70 and $100.

BTW, a PT-19 would barely fly in Santa Fe, New Mexico (7000 feet above sea level), where I spent my summers between 5th grade and college. One had to put a Tee Dee dual-port cylinder and a Medallion medium compression or Tee Dee high compression head on the engine to get it to work right. The P-40 already had the dual-port cylinder and so did better. My first RC airplane (Top Flite Schoolboy) was a kit designed for a TeeDee .010 but I had to put an .049 on it in Santa Fe, with the attendant weight and balance issues.

The rockets didn't care . Electric airplanes, with appropriate choice of propellers that are different from those for sea level, don't care about the altitude much.
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  #17  
Old 05-04-2009, 01:44 PM
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BEC BEC is offline
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Quote:
Originally Posted by ghrocketman
but 6,600 RPM is NOT going to fly any aircraft at what I'd call a reasonable speed unless you are using about 15" of pitch.


And on an appropriately chosen motor that's exactly what one would do - use a 15 inch pitch prop. Small diameter low pitched props are not the most effective way to move an airplane, but that's what one has to do with a glow engine that has to be screaming to develop anywhere near its best power and which has a fairly narrow range of RPMs where that is the case.

Be thankful your neighbors like the sound of two-stroke dirt bikes. They are very ATYPICAL of neighbors of flying sites these days.
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  #18  
Old 05-04-2009, 02:41 PM
scigs30 scigs30 is offline
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Here I am in the late 70's on Christmas morning with my PT-19 and today with my Pt-19. It is hard to believe I was that young flying gas powered planes and model rockets. I think by today's standards this would have been considered child abuse.

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  #19  
Old 05-04-2009, 02:44 PM
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ghrocketman ghrocketman is offline
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I was VERY fortunate in my youth that my parents were able to get me into R/C aircraft flying when I was age 8 in 1978. By the time I was out of High School, I had almost 10 years of on/off stick time in R/C aircraft.
Back then, R/C equipment (other than the cheap Toys-R-Us type cars/trucks) was VERY expensive in relation to income compared to today. Back in 1978 a BASIC 4-channel radio setup with 4 servos and full nicads was over $200 in actual 1978 dollars. That same basic setup can be had for $130 actual 2009 dollars through Tower Hobbies. The $200 dollar 1978 radio is about equivalent to $600+ now or conversely the radio now for $130 would have been about $45 in 1978 dollars.
It is MUCH cheaper to be involved in ALL forms of R/C now than it was back then.
R/C engines back then were also much more expensive in relation to income. Kits were about the same.
I had C/L Cox and Testors airplanes the year before I got into R/C (the same year I got into rockets) but was quickly bored with the circular flight.
__________________
When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL
, if you have to ask what is "NORMAL" , you probably aren't !

Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, and HAVOC !

Last edited by ghrocketman : 05-04-2009 at 03:07 PM.
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  #20  
Old 05-04-2009, 02:51 PM
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rokitflite rokitflite is offline
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Quote:
Originally Posted by scigs30
Here I am in the late 70's on Christmas morning with my PT-19 and today with my Pt-19. It is hard to believe I was that young flying gas powered planes and model rockets. I think by today's standards this would have been considered child abuse.



You should have been in the second picture wearing at least the same color clothing and with the same pose!
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