LDRS 26- AHPRA Bowling Ball Loft

[Mark Clark]

AHPRA will be holding the Bowling Ball loft at LDRS 26. The event will be H Lite Duration. Eight lb balls for maximum time on a parachute. We held this event last year in TX and it was a big hit with bowling Balls thermaling in the sky.
For more information go to https://www.ahpra.org/bowlingball7.htm

Mark

 

[denverdoc]

From the lack of interest, maybe time to consider something simultaneously more sane and challenging?

 

[cjl]

The problem I see with H bowling ball is simply that it's next to impossible to get any reasonable altitude out of it. Sure, the really fast H motors can pick up a bowling ball, but the impulse limits it to a couple hundred feet at most. I think a better event would be something with a bit more altitude potential. J or K power, possibly K heavy altitude? That has the potential for 6-7k with the right design...

As for big hit - weren't there only something like 3 or 4 entries last year?

 

[AZ_Ron]

Not sure of the altitude, as it was the H-Lite Duration that was held at LDRS last year, but the winner had a hang time of 1 minute 56 seconds... for an 8lb ball, it must have reached a decent altitude...

R

 

[rdbones]

My thought is that maybe it is too challenging ! Not enough people feel they can win so they dont want to play.

I am working on a design for the event, and hoping to have it done in time for LDRS - I am envolved in several other big projects so I dont know how much time I can spend on this one for personal gain.

a few of the sims I have are showing between 110 -140 seconds hang time and one other is showing 300 seconds (but I think that is incorrect!)

 

[AZ_Ron]

There is still a lot of 'knee-jerk' reaction to lofting "A BOWLING BALL!!! OMG!!"
Yet when someone flies a huge Phoenix, or Bullpup that has 15lbs of lead in the nose, nobody thinks twice about it.
Mark has made a few compromises and gotten to where the H-Lite is a very doable contest. Doesn't get a lot of altitude, the rocket/ball are in sight the entire time, etc.
I think you're right though Roy... there is a serious challenge to get as much altitude as you can and pack a large chute into a small airframe.
Mark has done a FANTASTIC job of getting prizes for the contest...
Check out www.ahpra.org and look at the BB Loft page...it lists how everyone finished at LDRS last year, and the prizes everyone won...
You could have easily had TWENTY people enter and EVERYONE would have gotten something... With the handful of people who are entering, they're making out like bandits!!!!
C'mon people... give this challenge a shot... Eggs are no challenge for HPR, and Ostrich eggs are hard to come by... go to the local Goodwill store and pick up an 8lb ball and come give it a shot!

Ron

 

[gonogo]

sshh... Ron dont attract to much attention, was hoping to make out like one of those bandits myself, even if I come in last. Seriously from the looks of it there were more than enough prizes to around and due to the low number of contestants all the winners walked aways with gobs of winnings. Ive allready pulled some parts together to build mine. Another idea for aquiring a ball is to check out your local bowling alley, ask if they have any they are willing to part with.

 

[Mark Clark]

We have been doing this for quite a while now. It has gone through a number of different motor/ball combinations. For launches at LDRS’s we started with K motors and 8 lb balls and the performance was higher than desired. The following year we doubled the weight of the ball but the competitors had improved an equal amount ant they still went very high. For the smaller launch site in New York we went back to 8 pounds but with an I motor, this event is the reason AT I600R and CTI I540 exist. At LDRS 24 we were approached by Gary from AeroTech with the idea of doing the H motors and he would make us motors (the H999), we talked it over and agreed to give it a try. The other motor manufactures were told; CTI and Loki made suitable motors, H565 and H500, at the time AMW did not make motors that small. We have gone to doing duration due to issues with altimeters and getting questionable readings. With PD anyone with a watch can get good and accurate results.

In Texas we had 4 entries actually launched out of 15+ who had contacted me saying they were for sure going to compete. Rockets went typically went 3-500’ with the exception of one rocket that was heavy. The winning entry at one point was going up in a thermal, and the crowd went wild.

As for too heavy it is the same power to weight as a NAR C Dual Egg Loft. Yes it is a challenge; yes it does not go very high. But the entire flight is visible and there is no chance of lobbing a gutter ball into the crowd (we have always requested to launch from the away cells). I believe using the techniques developed by the NAR Egg Lofters (Big hint here, find one of these guys and talk to him! Get him on your team!) Combined with the tremendous morning desert heating and resulting thermals at Jean an eight pound ball could stay up a very long time.


Or we could go back to the first time with motor unlimited, any size and number, 16 lbs for duration. No one can afford it and we did not give out prizes.

Mark

 

[denverdoc]

Originally posted by AZ_Ron
There is still a lot of 'knee-jerk' reaction to lofting "A BOWLING BALL!!! OMG!!"
Yet when someone flies a huge Phoenix, or Bullpup that has 15lbs of lead in the nose, nobody thinks twice about it.
Mark has made a few compromises and gotten to where the H-Lite is a very doable contest. Doesn't get a lot of altitude, the rocket/ball are in sight the entire time, etc.
I think you're right though Roy... there is a serious challenge to get as much altitude as you can and pack a large chute into a small airframe.
Ron

Well my rxn wasn't knee-jerk, tho I do have issus with the safety, having seen balls come down untethered--but if done on H from the away cells, I don't have any problems with the safety here.

Just wondering if there might be some interest in another contest for a change, as the rockets used tend to require more work, are single prupose, and so maybe not much incentive if your plate is fairly full building other things.
JS

 

[cjl]

How is that any more dangerous than any other 15+lb rocket if the recovery system fails? If anything, it's less dangerous because it's less aerodynamic. Sure, large objects thrown high in the air can be dangerous, but do you propose a ban on all rockets over 10 pounds?

 

[falingtrea]

Originally posted by Mark Clark
We have been doing this for quite a while now. It has gone through a number of different motor/ball combinations. Mark

Been about 10-12 years now, hasn't it Mark? I seem to remember a couple of flights at the Ironwood site.

 

[denverdoc]

Originally posted by cjl
How is that any more dangerous than any other 15+lb rocket if the recovery system fails? If anything, it's less dangerous because it's less aerodynamic. Sure, large objects thrown high in the air can be dangerous, but do you propose a ban on all rockets over 10 pounds?

As I have posed several times before, I believe there are safer payloads than bowling balls. Not going to rehash those arguments here, just wondering if there might be any interest in doing something else--apparently the answer is no.

So who knows, maybe I'll give it a try. Thought about it last year, but other projects took priority.

J

PS: As to less aerodynamic, maybe if compared to a lawn dart, but multiple modes of failure in a conventional rocket that would land a lot less forcefully--in fact just about any failure short of a lawn dart, as most parts tumble or spin and have a smaller effective ballistic coefficient than a high density sphere.

 

[falingtrea]

Originally posted by denverdoc
As I have posed several times before, I believe there are safer payloads than bowling balls. Not going to rehash those arguments here, just wondering if there might be any interest in doing something else--apparently the answer is no.

The club I was a member of once did water lofting at one time. It is nice that a liter of water is exactly 1 kg, and a gallon is a little more than 8 lbs. I don't know how much safer water lofting would be than bowling ball lofting. Guess it would depend on the container. Might be interesting to see if you could loft water in a balloon and keep it intact. Might be more challenging than egglofting.

 

[denverdoc]

Originally posted by falingtrea
The club I was a member of once did water lofting at one time. It is nice that a liter of water is exactly 1 kg, and a gallon is a little more than 8 lbs. I don't know how much safer water lofting would be than bowling ball lofting. Guess it would depend on the container. Might be interesting to see if you could loft water in a balloon and keep it intact. Might be more challenging than egglofting.

Thats interesting, I considered water and sand, never known that one has been tried. I like the balloon idea a bunch.
JS

PS: we are trying to take egg lofting out here in colorado to new heights in conjunction with an H999 mandatory motor.

 

[The Visionary]

Ya'll have got to be kidding me... You are telling me that no one here wants to see what kind of crater a 16lb bowling ball would make from around 5000'. That would just be awesome. :kill:

Personally, I am almost offended as a bowler that someone would do such a thing to a bowling ball. People spend hundreds of dollars on them. Show a little respect.

ROFL

Comic relief... I feel better now.

 

[AZ_Ron]

But we buy them from the thrift store, so in essence, we're giving them a new life!!!

 

[gonogo]

for cryin out loud people its just a simple payload loft. 8lb on a chute. my lvl 2 bird weighed more than that. its cheap and simple. pull some parts together and compete. blah blah blah its too hard, blah blah blah its to dangerous, its a challenge isnt that what makes this hobby fun? would you rather have that 8lb in the form of a butterfly or a unicorn? its a round piece of mass just get it up and get the chute out. its not a WMD.