You might be a child in the 70s if:

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This represents growing up in the 70's to me. Centuri rockets! Growing up in the southern plains, we could buy Centuri rockets in our small town at TG&Y (or mail order the catalog from Boy's Life ads). In fact, I didn't even know Estes existed until I got back into rocketry in my late 20's and learned they had acquired Centuri.
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We had these, they were on control cables with a kite handle and you spun in a circle to keep it flying in a circle.

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I had one of those as well (sold into the '90s I believe). It flew 'OK', but the plastic was pretty heavy. Circles were fine, but I kept trying to get it to complete a loop and only getting 3/4 of the way around. At least it was durable. But balsa definitely flies better.
 
Shoot I'm not the OP. Male bees or drones are only kept around the hive to mate with a new queen if the old one dies or the hive decides to
swam and break apart and form a new hive. (Read about Royal Jelly for the queen stuff). Once mated, the queen can store the
sperm for the rest of her egg laying days. Male bees or drones are redundant after she's mated. A new queen goes on a "honeymoon" flight
and the toughest drone who can catch up to her gets to mate! Sounds funky to me! Drones are so useless except to keep male DNA around that
they HAVE TO BE FED by the worker bees! (Sterile females) They can't feed themselves. Any excess males/drones lying around at the end of the season get unceremoniously dumped out of the hive by the workers to freeze to death! More drones can be had by allowing an unfertilized egg to develop. That becomes male. Fertilized eggs become workers or a queen if the need develops.
Just so. And here's another one that probably belongs in the nerdy facts thread; when a queen goes on a mating flight, drones from other colonies* show up along with her own. That keeps up genetic diversity; without it, all the bees in one colony would be genetically identical.

* A hive is place that bees live. The bunch of bees who live there is a colony.
 
Was there a girls life?

But seriously:

The American Girl

From 1917 until 1979, Girl Scouts published a magazine, originally called The Rally (1917–1920) and then The American Girl, with "The" later dropped. (It is not to be confused with the American Girl magazine 1992–2019.) Circulation exceeded 200,000 in the 1940s, and reached as high as 510,000 per month by 1949. At that time, the popular Seventeen had 2.5 million readers. In 2005, this magazine had the largest circulation of any magazine aimed at teen-aged girls.
OK, so it had lower circulation than Seventeen. I bet Boy's Life had lower circulation than covertly shared issues of Playboy.

(And if you ask "What was Playboy" then I give up.)
 
I loved World! I wish there was something like that for kids today. Now there's Nat Geo Kids, but it doesn't seem to be the same... or maybe it's kids that have changed but it totally fails to be interesting to my almost seven year old.
 
Yes, you did. Where it was going to go was into a tree!

We had one growing up in New Mexico, and it never really flew, it would just skip along the ground. Then we moved to New Jersey, and it flew great* there!

*Except for the tree thing. We lived near a giant field that was clear except for one tree in the middle. Every rocket, kite, plane, or flying saucer we flew ended up in that tree!
This information is decades too late but — the way to get that saucer (or a Cox PT-19) to fly at high altitude (I lived in Santa Fe in the summer back then) was to go to the hobby shop and get a piston/cylinder set for a Tee Dee .049 and put that on the engine in the model. Fortunately it swaps right in. That cylinder gives you two bypass ports vs. one, and the piston, I think, also gives a slightly higher compression ratio. It also helped to use something like Fox Missile Mist or Cox Racing Fuel, both of which had a higher nitro percentage than the regular Cox blue label fuel (if I remember correctly, Missile Mist was 40% nitromethane).

Between the higher altitude air having less oxygen so the engine developed less power and the higher altitude less-dense air so the prop needs to spin faster to generate the same thrust, it was a real challenge to get models like that which flew at sea level just fine to fly in NM, especially the higher elevations.

On an electric-powered airplane, by contrast, all you need to do is put on a prop with a little more pitch (and watch the stall speed of the airplane)….to get most of the sea level performance back. The motor doesn’t care about the altitude.
 
The motor doesn’t care about the altitude.
They actually do. Higher altitude is less dense air so convective cooling is less efficient due to lower mass flow rates over the windings.

If the motor has plenty of design margin or you don't push it too hard it doesn't matter. If you push it too hard for a short time it doesn't matter (thermal inertia).

Push it past its limit and generally the insulation breaks down. Once you have a shorted turn things go south very quickly.
 
Between the higher altitude air having less oxygen so the engine developed less power and the higher altitude less-dense air so the prop needs to spin faster to generate the same thrust...
And you should expect to need more thrust, not the same thrust as at sea level, because the less dense air means to need more speed to get sufficient lift.

Push it past its limit and generally the insulation breaks down. Once you have a shorted turn things go south very quickly.
After it briefly goes north. Short out one or two turns and you get lower back EMF, so the motor speeds up. Until it smokes.
 
They actually do. Higher altitude is less dense air so convective cooling is less efficient due to lower mass flow rates over the windings.

If the motor has plenty of design margin or you don't push it too hard it doesn't matter. If you push it too hard for a short time it doesn't matter (thermal inertia).

Push it past its limit and generally the insulation breaks down. Once you have a shorted turn things go south very quickly.
Well, OK. But compared to an internal combustion engine in a model airplane, the effects on a motor are small….until they aren’t as you point out. I don’t know about current products on the market (as getting back to rockets pretty much pulled me out of RC aircraft activity) but when I was active the motors that I flew had plenty of margin for this case.

And you should expect to need more thrust, not the same thrust as at sea level, because the less dense air means to need more speed to get sufficient lift.
Not more thrust, more pitch speed, which is why I posted (and have verified by testing both near sea level and at 7000 feet in Santa Fe) that putting on a prop with the same diameter and more pitch pretty much restores the airplane’s performance through most of the flight envelope.

More airspeed is definitely needed really even if static thrust is lower. And I’m sure there are extreme examples where this simple change doesn’t work, but for the models I flew, it worked very well. Best results were had when the higher-pitched prop pulled about the same current statically as the “regular” prop did at home (near sea level).

No amount of power system tweaking helps with the higher stall speeds, though. One simply has to fly the airplane with that in mind.

I never repeated this sort of testing (same airplane, same motor/battery, different prop depending on MSL of the flying site) using onboard data loggers. Hmmmmm….
The biggest impediment to doing that now is that both companies who made onboard loggers I use (Medusa Research, Eagle Tree Systems) are out of business and their software applications for downloading and interpreting the data don’t play nice with current versions of Windows and I haven’t set up a dedicated machine with XP on it to use just for this purpose.

But as I type this I realize that I do have a way to do this via Emeter II and its data units that can be put aboard a model. No Windows required to get the data out of that setup. Hmmmmm again.

The other limiting factor is propeller selection….similar props with different pitches. At least for the smaller models I have closest to flyable, there aren’t lots of choices in that area. It’s kind of like not being able to get the delay you need for your rocket in single use motors.
After it briefly goes north. Short out one or two turns and you get lower back EMF, so the motor speeds up. Until it smokes.
Fortunately, I’ve never pushed one that far.
 
I loved World! I wish there was something like that for kids today. Now there's Nat Geo Kids, but it doesn't seem to be the same... or maybe it's kids that have changed but it totally fails to be interesting to my almost seven year old.
Same here. My 9YO really is into geography and most anything with other places. I figured Nat Geo for kids would be right up his alley.
He found it boring and I found it lacking in any stimulation. I canceled it.
 
This information is decades too late but — the way to get that saucer (or a Cox PT-19) to fly at high altitude (I lived in Santa Fe in the summer back then) was to go to the hobby shop and get a piston/cylinder set for a Tee Dee .049 and put that on the engine in the model. Fortunately it swaps right in. That cylinder gives you two bypass ports vs. one, and the piston, I think, also gives a slightly higher compression ratio. It also helped to use something like Fox Missile Mist or Cox Racing Fuel, both of which had a higher nitro percentage than the regular Cox blue label fuel (if I remember correctly, Missile Mist was 40% nitromethane).

Between the higher altitude air having less oxygen so the engine developed less power and the higher altitude less-dense air so the prop needs to spin faster to generate the same thrust, it was a real challenge to get models like that which flew at sea level just fine to fly in NM, especially the higher elevations.

On an electric-powered airplane, by contrast, all you need to do is put on a prop with a little more pitch (and watch the stall speed of the airplane)….to get most of the sea level performance back. The motor doesn’t care about the altitude.
Thanks for sharing that. I flew control line in the Midwest and I was unaware of the high altitude flying and performance. I used the Thimbledrone fuel in my Babe Bee motors and "normal" fuel in my 0,35. Nitro methane would be good for high altitude, but I was always cautious about using it. Missile Mist (40% nitro) was always on the hobby shelves but i thought it was just used by contest flyers, or people trying it out before buying a bigger motor.
 
Well, OK. But compared to an internal combustion engine in a model airplane, the effects on a motor are small….until they aren’t as you point out. I don’t know about current products on the market (as getting back to rockets pretty much pulled me out of RC aircraft activity) but when I was active the motors that I flew had plenty of margin for this case.


Not more thrust, more pitch speed, which is why I posted (and have verified by testing both near sea level and at 7000 feet in Santa Fe) that putting on a prop with the same diameter and more pitch pretty much restores the airplane’s performance through most of the flight envelope.

More airspeed is definitely needed really even if static thrust is lower. And I’m sure there are extreme examples where this simple change doesn’t work, but for the models I flew, it worked very well. Best results were had when the higher-pitched prop pulled about the same current statically as the “regular” prop did at home (near sea level).

No amount of power system tweaking helps with the higher stall speeds, though. One simply has to fly the airplane with that in mind.

I never repeated this sort of testing (same airplane, same motor/battery, different prop depending on MSL of the flying site) using onboard data loggers. Hmmmmm….
The biggest impediment to doing that now is that both companies who made onboard loggers I use (Medusa Research, Eagle Tree Systems) are out of business and their software applications for downloading and interpreting the data don’t play nice with current versions of Windows and I haven’t set up a dedicated machine with XP on it to use just for this purpose.

But as I type this I realize that I do have a way to do this via Emeter II and its data units that can be put aboard a model. No Windows required to get the data out of that setup. Hmmmmm again.

The other limiting factor is propeller selection….similar props with different pitches. At least for the smaller models I have closest to flyable, there aren’t lots of choices in that area. It’s kind of like not being able to get the delay you need for your rocket in single use motors.

Fortunately, I’ve never pushed one that far.
I'm a little lost. Since you need to go faster through the air, doesn't that mean you need mor force pulling you along, i.e. more thrust? What is that greater pitch getting you if not more thrust?
 

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