Take off distance in j4xx

Australian designed and manufactured Jabiru Aircraft/

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ZuluBen
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Re: Take off distance in j4xx

Unread post by ZuluBen » Tue Sep 15, 2009 7:20 pm

Hi Wynand

Looking forward to the balloon, never aviated in one of those devices!

And those steaks sound lekker!

OK, Henk, ons is reg, make it happen!

PS
Brilliant "Coastal" post, enjoyed that.
It is very important to buy your fresh stock of memory pills before you run out completely ...
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Re: Take off distance in j4xx

Unread post by BenSmit » Tue Sep 15, 2009 10:39 pm

No rudder, no motor, I will drive the bakkie and pick you up thanks
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henk-indabush
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Re: Take off distance in j4xx

Unread post by henk-indabush » Wed Sep 16, 2009 7:13 am

Thanks Wynand, appreciate it lots! I will sleep on a couch, no problem.
The 3 things we need for such an excercise is Avgas, sandbags (do ballooners still use them?) and different airfields.
Airfields within short distance of each other, with as much QNE variation as possible, and different surfaces. If you all can perhaps help in advising airfields, please? I do not know the area, my knowledge extends as far as easyplan.
I suggest we book provisionally 6 -8 Oct (2 nights, arrive 6th depart 8th) with the scope to move it forward or backwards in time (a day or so) according to what the weather allows. I suppose Wynand's busy times are over weekends, hence I would prefer to have it during the week.
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wynand
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Re: Take off distance in j4xx

Unread post by wynand » Wed Sep 16, 2009 8:46 am

Makes little diff to me whether weekdays or weekend. Let the weather decide.
I've provisionally reserved place at my lodge the nights of 6,7 and 8 Oct for the Jabiru trials. We can adapt to the weather.
I have 6 rooms available, total 12 beds.
Pm me for cost. I can't disclose the cut-rate tariffs here.

We don't really have suitable strips other than Hoedspruit Civil, but the DA does change a lot during the course of a sunny day.
Of course, there's Graskop (for higher alt), but I'd have to go check the rwy surface. I'm told its potholey, and it is really too short at 800m for MTOW trials.
Hippo Pools is a short hop away, but it has gradient and I wouldn't want to do MTOW there on a hot day.

Those that want to get the feel of a real "bush strip", just for fun, there's Xanatsi. Delightful, but we won't really learn anything because the elevation is the same as Hoedspruit.

There's big asphalt at Phalaborwa (1300m and elevation 1400ft), but we'd be looking at 24hr prior notice and landing fees. Perhaps Willie (who flies everything but Jabi's) can facilitate something there.

Oh, and there's Pilgrims Rest! Now that could be useful: 1500m of asphalt at elev 3600ft and I can't recall that it has gradient. I'll find out if Barloworld will let us use it.

Ja, between Hoedspruit Civil and Pilgrim's we could do some useful work.

We don't have to re-invent the wheel, you know. If we can get some good data points at DA of 3000ft, and again at DA 6000ft, we can interpolate and extrapolate with the usual DA-performace graphs.
I think the biggest factors (other than DA) causing variance in performance (and headaches for us) will be prop pitch and take-off technique.
Wheel size and inflation pressure would be additional complicating factors not to mention engine tuning and age of engine.
Wind, and gradient factors would the same as other aeries?

And BenSmit, you'd be surprised how well one can steer a balloon just by "going with the flows".

Lastly: Avgas. #-o
I'd have to work on that.
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henk-indabush
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Re: Take off distance in j4xx

Unread post by henk-indabush » Wed Sep 16, 2009 9:55 pm

wynand wrote:Makes little diff to me whether weekdays or weekend. Let the weather decide.
We don't have to re-invent the wheel, you know. If we can get some good data points at DA of 3000ft, and again at DA 6000ft, we can interpolate and extrapolate with the usual DA-performace graphs.
.
Fully agree. And I do not want to let all the planning etc come down on you, so let us know where we can assist. We do not need full tanks on each T/O, I was more thinking on the line of having 3/4 tanks and make up the rest with sandbags. Much safer that way. Best runway would of course be a long tar one on which one can land again if T/O partly unsuccessfull! But Hoedspruit and Pilgrims will do perfectly. And perhaps a grass runway thrown in for good measure. One can learn a lot from data - same weight at Graskop and Hippo pools, say 100 kg's below MAUW, and we can learn n lot from that, if the ground run is measured accurately. I think this excercise is more to determine accurate ground run distances than pushing the MAUW performance. Once we have the accurate distances we can extrapolate a lot.
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Re: Take off distance in j4xx

Unread post by ZuluBen » Wed Sep 16, 2009 10:03 pm

BRING IT ON !!!
It is very important to buy your fresh stock of memory pills before you run out completely ...
INVEST IN AFRICA, BUY A POLITICIAN!
Now a legal UFO driver as well !! A2 - UFO
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wynand
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Re: Take off distance in j4xx

Unread post by wynand » Thu Sep 17, 2009 8:07 pm

Henk, I can do sand bags.
What denomination?
10kg?
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Re: Take off distance in j4xx

Unread post by henk-indabush » Fri Sep 18, 2009 9:58 pm

Will appreciate if you can do the bags - either 10 or 20 kg's will do.
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Re: Take off distance in j4xx

Unread post by peterd » Sun Sep 20, 2009 10:57 am

we used 2 x 25 l water cans . it is easier moving around and you can vary the weight by placing markers up the side of the water can. Also less messy = would not want sand bags in the plane
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Re: Take off distance in j4xx

Unread post by henk-indabush » Sun Sep 20, 2009 9:32 pm

Indeed it makes sense to use water cans. I was thinking of putting the sandbags in black bags to prevent any messing. Surely we can use whichever method is easier for Wynand, I can bring along a few empty water cans, no problem.
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Re: Take off distance in j4xx

Unread post by wynand » Mon Sep 28, 2009 11:18 am

OK, folks!
The time is drawing near.

Let me know who's coming. I have to start pegging down the reservations at the lodge.
I still have 4 units available
6 and 7 October.
or
7 and 8 October
we'll keep it flexible to allow for weather.

PM me for costs. Yes, there are some, I'm afraid, but not too much.
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Re: Take off distance in j4xx

Unread post by ZuluBen » Mon Sep 28, 2009 6:14 pm

Me and softness is taking one !!

And you better have the gas tanks on that balloon filled up Ouboet!
It is very important to buy your fresh stock of memory pills before you run out completely ...
INVEST IN AFRICA, BUY A POLITICIAN!
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wynand
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Re: Take off distance in j4xx

Unread post by wynand » Mon Sep 28, 2009 6:37 pm

ZuluBen wrote:Me and softness is taking one !!

And you better have the gas tanks on that balloon filled up Ouboet!
Thats the spirit Z-Ben!

All three balloons with full tanks, champagne chilled and light airs ordered.

Just you make sure to arrive thirsty and hungry.
Hope you're not vegetarian.
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ZuluBen
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Re: Take off distance in j4xx

Unread post by ZuluBen » Mon Sep 28, 2009 8:10 pm

Wynand wrote:
Hope you're not vegetarian.
Small chance! :lol:

I have taught my children the following line thoroughly: "Man did not claw his way to the top of the food chain to eat plants!"

Looking forward to this!
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Re: Take off distance in j4xx

Unread post by wynand » Fri Oct 02, 2009 2:37 pm

So. it looks like Henk, ZuluBen and Mrs ZuluBen coming to Hoespruit so far...

6 and 7 October.
or
7 and 8 October
we'll keep it flexible to allow for weather.

Any more takers?

I've been in contact with the Pilrims Rest FAPO airstrip manager.
I have the indemnity forms that we have to complete and return with R300 landing fee :shock: , 2 days before arrival...
Its a bit costly, hey? Still, I'd like to go, if you guys don't mind. Its a beautiful spot.

I'm investigating alternative strips.
"Rule books are paper. They will not cushion a sudden meeting of stone and metal." -Ernest K. Gann

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