5,000 Feet Mid-Powered... Possible?

[Bruiser]

A few days back I posted in the "What Did You Do Rocket Related Today" thread that I had a dream I built and flew a rocket to 5,000 feet. I don't know what brought it on but it did get me thinking. So much so that I opened a few designs I have slated for this year and ran sims with "H" motor but nothing came close.

I googled "5,000 foot rocket" today and the Apogee Aspire popped up. Apparently it will do it using one of Apogee's 29mm F motors if you leave the launch lugs off. They recommend making it dual deploy but I didn't see if it would still make 5,000 feet with the extra weight. They say it can go supersonic too which really surprised me since it has surface glued balsa fins...

Are there any other designs that can make it to 5,000 feet using mid-power?

One other question... I was thinking that maybe it could separate midway and utilize

Thanks,
-Bob

 

[cbrarick]

blackhawk 24 with G145 pink 5678 feet

 

[heada]

The F10 is a good motor but Aerotech has released a few that'll send that same Asipre higher. G12ST-P Should come closer to 6000 feet but would require electronic deployment since it's a plugged motor.

Rockets that small and that high would be impossible to visually track so you'd want electronics anyway.

 

[CalebJ]

The F10 is a good motor but Aerotech has released a few that'll send that same Asipre higher. G12ST-P Should come closer to 6000 feet but would require electronic deployment since it's a plugged motor.

Rockets that small and that high would be impossible to visually track so you'd want electronics anyway.

Isn't there a long burn plugged 29mm H motor as well? Seems to be I simmed one in an Aspire one day when tinkering in Open Rocket.

 

[dhbarr]

blackhawk 24 with G145 pink 5678 feet

g65 in Mach1 glass ( have them spin you a 24mm Mamba or Alien Interceptor ) if you want to avoid high power.

 

[heada]

Isn't there a long burn plugged 29mm H motor as well? Seems to be I simmed one in an Aspire one day when tinkering in Open Rocket.

Indeed but an H is no longer MPR. There are actually 2 long burn G motors. G12 and G8. Not sure if the G8 would have the power to lift it.

 

[waltr]

Here is one I just put together in Open Rocket. 5526 feet on a G25 or 5912 on a G75. Both 29mm.
Did include an H motor even though it makes this a HPR.

 

[green dragon]

G08 will fly an Aspire all day.... I fly them regularly in BT70 based ''Cloud 9' rocket.

Get in on the Hamster Dance activites for BALLS, lot of altitude going on there with small rockets.

 

[Jmhepworth]

Not midpower, but I flew an Aspire to 9,000 feet on an H13. It has to be dual deploy because the H13 doesn‘t have an ejection charge.

 

[heada]

An Estes Star Orbiter with an Apogee BT50 av-bay, Eggtimer Quark with a 2S 300mAh lipo and the G12 or H13 should go well beyond 5000' on a complete stock build with dual deploy. Entire build for less than $100

 

[teepot]

Make a 15 ounce 29mm MD and put a G80 in it and it will make 5000'. But just barely.

 

[Scott_650]

A few days back I posted in the "What Did You Do Rocket Related Today" thread that I had a dream I built and flew a rocket to 5,000 feet. I don't know what brought it on but it did get me thinking. So much so that I opened a few designs I have slated for this year and ran sims with "H" motor but nothing came close.

I googled "5,000 foot rocket" today and the Apogee Aspire popped up. Apparently it will do it using one of Apogee's 29mm F motors if you leave the launch lugs off. They recommend making it dual deploy but I didn't see if it would still make 5,000 feet with the extra weight. They say it can go supersonic too which really surprised me since it has surface glued balsa fins...

Are there any other designs that can make it to 5,000 feet using mid-power?

One other question... I was thinking that maybe it could separate midway and utilize

Thanks,
-Bob

Just playing around with Thrustcurve - you’ll have a challenge keeping a lightly built Apogee Aspire under 1500 meters on a G motor

Bumping up to an Estes Star Orbiter would make the packaging simpler and it should hit your target altitude easily on either of the single-use Aerotech G80s and it sims pretty close on a G78 - again, if it’s kept light and the finish smooth.

As already suggested, unless you’re planning on a fire and forget flight, some kind of electronics is going to be needed. I know folks manage to get reliable recoveries with a Jolly Logic Chute Release in BT-60 rockets - I can’t quite get the bundle packed well enough myself but I’ve witnessed it work at club launches - as already mentioned you can’t get much lower cost to capability than a build it yourself Quark from Eggtimer.

Fun mental exercise that could fairly easily be made into a practical project…

 

[BigMacDaddy]

Would you be willing to do a two-stage rocket? I have never done anything at this level but a BT-55 rocket with two stages of F15 Estes engines seems to sim over 4500ft.

 

[caveduck]

Single stage 24mm F32, minimum diameter, no lugs, slick finish, optimum mass, tower launch, will get you close to 5400' according to OpenRocket. I'd try something like a 4" x 30ft mylar streamer to get it back. Might be a fun project for LDRS now that it's in my back yard.

 

[Bruiser]

I was wondering if a Star Orbiter would do it. I found and downloaded a .ork file for it last night and stated plugging some H motors in but none of the motors I saw in OpenRocket that I choose did it. I now know that a long burn motor seems to be the key

Actually I have a IQSY Tomahawk I bashed from a Star Orbiter. It's shortened to 27.5 inches tall and has four fins. It was my first BAR build. https://www.rocketryforum.com/threads/iqsy-tomahawk-sport-scale-bash.146392/ I'll have to put it in OpenRocket and see what it could do just for gee whiz. The thing is that I am not Level 1 certified...

Heada wrote "An Estes Star Orbiter with an Apogee BT50 av-bay". Did you mean a BT50? That confuses me a bit because the Star Orbiter is a BT60 rocket.

 

[CalebJ]

I was wondering if a Star Orbiter would do it. I found and downloaded a .ork file for it last night and stated plugging some H motors in but none of the motors I saw in OpenRocket that I choose did it. I now know that a long burn motor seems to be the key

Actually I have a IQSY Tomahawk I bashed from a Star Orbiter. It's shortened to 27.5 inches tall and has four fins. It was my first BAR build. https://www.rocketryforum.com/threads/iqsy-tomahawk-sport-scale-bash.146392/ I'll have to put it in OpenRocket and see what it could do just for gee whiz. The thing is that I am not Level 1 certified...

Heada wrote "An Estes Star Orbiter with an Apogee BT50 av-bay". Did you mean a BT50? That confuses me a bit because the Star Orbiter is a BT60 rocket.

A Star Orbiter wasn't hitting 5k on an H? What was the configuration for delay? Sounds like it was deploying during ascent in Open rocket.

 

[Bruiser]

I think one was a H128 and the other was a H238 if I remember right. Your guess was right at first. I didn't select the delay but then I saw it was opening too early so I went back and changed them from the auto populated 6 to the 10. I think they both simmed in the low 4,000 foot realm after that.

I also didn't review the sim I downloaded for accuracy as I really didn't know what the weight, cp or cg should actually be.

We have a Hobby Lobby in town so I could pick up a Vapor today. I have centering rings and decals left over from old Star Orbiters I used for parts (they made real nice donor kits and were cheap at HL when they carried them) and I have some 29mm pro series engine tubes and retainers. I wonder if cutting fins out of 1/16th ply would help?

-Bob

 

[CalebJ]

You're right - I misremembered the numbers for the Star Orbiter. Just grabbed my laptop and checked the numbers on my own sim file for the H128 and 238. I'm only getting about 3600 feet for each.

 

[Bruiser]

From what I'm learning on this thread it's because they are pretty short burn motors (1.3 and .7 respectfully). I'm gonna try simming it on a G25 (4.2) tonight on my laptop (that's where OR is installed.

I might also try down-sizing to a BT-55 airframe, lose the retainer, change fins to 1/16th ply and see what happens with a G25.

-Bob

 

[BEC]

The top four finishers in C division E Altitude (with altimeter) at NARAM 61 at Muncie (2019) all flew higher than 5000 feet, as did the first place finisher in Team (D division). We all used Apogee E6-8s.

https://www.nar.org/site/naram-61-r...lying-info/naram-contest/naram-61-e-altitude/. (5000 feet is 1524 meters)

Drag is your enemy for altitude, so long, slow burns are the way to go. Drag increases with the square of speed, remember.

Jonathan Rains demonstrated this aptly by blowing the 2nd-4th place finishers away at NARAM-61. His model was beautifully smooth and the nose cone to body joint was almost invisible. So he beat the next finisher by almost 300 feet. As I say, all of us were using Apogee E6-8s.

My model, the third place finisher, was basically a slightly stretched Alpha with thin carbon fiber fins (smaller than those on a regular Alpha). I even used an Alpha VI nose cone, which was a good place for 1/4 ounce of ballast and the altimeter. In playing with OR in designing the thing, I learned that a little more mass was a good trade for a shorter body and smaller fins to reach the needed stability while reducing drag. In models that size, the 8 second delay is too short….

 

[Lord Rory Gin]

A few days back I posted in the "What Did You Do Rocket Related Today" thread that I had a dream I built and flew a rocket to 5,000 feet. I don't know what brought it on but it did get me thinking. So much so that I opened a few designs I have slated for this year and ran sims with "H" motor but nothing came close.

I googled "5,000 foot rocket" today and the Apogee Aspire popped up. Apparently it will do it using one of Apogee's 29mm F motors if you leave the launch lugs off. They recommend making it dual deploy but I didn't see if it would still make 5,000 feet with the extra weight. They say it can go supersonic too which really surprised me since it has surface glued balsa fins...

Are there any other designs that can make it to 5,000 feet using mid-power?

One other question... I was thinking that maybe it could separate midway and utilize

Thanks,
-Bob

I've got an 8.5 oz Mad Cow cardboard Black Brant that should get to 5600' on a G159

 

[GrouchoDuke]

You can definitely hit 5k with a mid power rocket. It should be pretty doable with almost any min-diameter 24 or 29mm rocket and G motor. (Just don't make the rocket any longer than you need and don't have draggy things like launch lugs on it.) The F10 is a great motor for this too. Just make sure you have a good tracker & know how to use it!

 

[Bruiser]

BEC, what did you do for recovery?

I played around a bit in OR last night modifying a Star Orbiter. I scaled it to a BT55 tube and that helped. Then I shortened it a bit and that helped more but still not quite enough. Then I scaled it to a 29mm motor tube and that helped more. I remembered BEC's post "more mass was a good trade for a shorter body and smaller fins" so I added some nose weight and reduced the fin size and I was hitting 5,300 feet with the G25. I do need to turn the coupler into a AV bay and add the extra weight involved in that.

-Bob

 

[waltr]

In OR use the "Tools/Rocket Optimization" to auto adjust parameters for altitude.

That is what I did for the OR model I posted above and got 5526 feet on a G25.

 

[BEC]

BEC, what did you do for recovery?

Shiny streamer and the good graces of other competitors.

A model this small going that high simply disappears, so we were finding each other's models as we did our search patterns in the directions we thought they might have gone. It helped that the Contest Range was set up near the center of the International Aeromodelling Center and there was a huge area of mostly close-cut grass in which to search.

I actually found my own model after one of my two flights (in the rocks of a parking lot), but someone else found it after the other and brought it back to the range head.

Chad Ring was using a Walston tracker setup. I don't know if it helped him find his model any more quickly or not (since I spent lots of time that morning searching myself).

I've thought about trying to do a mile with a Star Orbiter but I keep seeing it go supersonic in simulations that have enough total impulse to get it there....and I'm not really looking to make one with glassed fins (which of course adds mass and drag) to get there and yet I am skeptical that 3/32 inch balsa would survive the transition.

 

[heada]

In these small rockets, you want a long burn motor with low average thrust. That's why the E6 and F10 are so popular. Rather than sending a Star Orbiter supersonic, look at the G12 with 12.7 seconds of burn. Or the G8 with 17 seconds. Mass optimized and low drag, those long burn motors should give a higher flight. The H13 is another option but that's HPR

 

[Jmhepworth]

An H13 in an Apogee Aspire is a class 1 rocket. Because the rocket with the motor weighs less than a pound and the total thrust is less than 160NS, it’s class 1. I suppose we would still call it high power because it’s an H motor that requires certification to purchase.

 

[heada]

An H13 in an Apogee Aspire is a class 1 rocket. Because the rocket with the motor weighs less than a pound and the total thrust is less than 160NS, it’s class 1. I suppose we would still call it high power because it’s an H motor that requires certification to purchase.

H13 is 211Ns total. It's well into the H range of >160 Ns and < 320 Ns. And it has a nice initial thrust spike of 45N to get it out of the tower and then 15 second burn to sustain. It falls in class 1 for FAA but needs HPR cert 1 or higher per NFPA. So no waiver but still HPR safety rules and cert.

This is about MPR hitting 5k+ feet so still going with the G12 or G8 on an optimized flight for best results.

https://www.thrustcurve.org/motors/AeroTech/H13ST/

 

[samb]

An H13 in an Apogee Aspire is a class 1 rocket. Because the rocket with the motor weighs less than a pound and the total thrust is less than 160NS, it’s class 1. I suppose we would still call it high power because it’s an H motor that requires certification to purchase.

Definitely high power as heada stated. Definitely FAA class 1 but not because of newton/seconds. The Class 1 threshold is propellent weight (125 grams) and/or total vehicle weight (1500 grams or 3.3 pounds). The FAA doesn't care about thrust.

 

[Jmhepworth]

Definitely high power as heada stated. Definitely FAA class 1 but not because of newton/seconds. The Class 1 threshold is propellent weight (125 grams) and/or total vehicle weight (1500 grams or 3.3 pounds). The FAA doesn't care about thrust.

Thanks. I knew it was class 1. I’d just forgotten why.