Cross country Question

[lazerq3 0]

OK...so I ,m planning on doing my first cross country and I'm trying to estimate the distance I'll travel......Can anyone here hepl me out.....(Quade).....heres what I have so far... I fly a Hor 150 @1.2:1 WL.....assuming I have a 3:1 glide ratio, from 8000ft to 0ft agl that should give me approx 24000ft of travel (4.5 miles) if I was in NO wind with a forward speed of 20mph... now throw in a 20mph wind ...(thats what our uppers have been around lately).....and running WITH it does that approx double the distance at a 40mph run speed so it'll be approx 9 miles????? I know the direction I want to go if the winds ever go that way because there our a LOT of fields to land in .....but if I can get close to the approx DIS it would help...am I just wasting time trying to fig this out????
jason

[SkydiveMonkey 0]

With X-countrys, do you get out directly over the DZ, or get out miles away and try to fly back?
Let's go play chicken with a planet !!

[nacmacfeegle 0]

Miles away, and fly back. In the UK you probably need some sort of ATC clearance or NOTAM or demo type paperwork.
Chat with your CCI and I'm sure he will try and talk you out of it, but will explain all......They are good fun, especially at sunset, with a wee tinnie or so stashed in the J/S Cya
D
GR# 37
Remember how lucky you are to see and touch the sky; the blind may only dream.

[lazerq3 0]

I talked to my DZO and he said they like to try and fly to the DZ but he also said it would be OK to get out over the DZ and just take off........Like I said the DIRECTION I want to go (if the uppers are going that way) is really safe.....lots of field and pastures!!!
jason

[SkydiveMonkey 0]

Our Dz is in the country, and there's fields for miles in every direction (apart from the sea about 4 miles away, but the wind ALWAYS come from that area). I'd love to do one sometime.
Let's go play chicken with a planet !!

[PhreeZone 20]

I did CReW last weekend with uppers at 40 knots. We went 4.5 miles out, poped at 13k, and turned around at 6000 since we had blown past the DZ already. We talked about going 6 out the next time. Have at least one person carry a cell phone and fly as a pack or a line, don't all head in different directions. Dress warm too, figure it is 25 degrees cooler at least at 8000 feet. I did one last year, jet pass out of the casa, poped on a 10 second delay over 6 miles out. Tagged the center of the disc in the Peas on my landing. Lesson learned... don't wear sandles unless its at least 100 on the ground. You have the air temp and wind chill to get to your exposed skin...
If once you start down the dark path, forever will it dominate your destiny, consume you it will....

[crazy 0]

Quote

OK...so I ,m planning on doing my first cross country and I'm trying to estimate the distance I'll travel......Can anyone here hepl me out.....

Easy, even with stupid units like feet vertically and miles horizontally :-)
First try to figure out the vertical speed (V) and horizontal airspeed (H) of your canopy in half brakes. Either measure it or take typical values (like V=10ft/s, H=14mph but these are arbitrary values and don't reflect the characteristics of your canopy).
Then you have to know the winds (W). Just take an average between the uppers and the winds at 2000ft, else you'll get headaches.
As you know your opening altitude (O), you can get the duration of the flight D=O/V. For instance, you open at 8000ft and your vertical speed is 10ft/s, the duration will be 800 seconds. This is the maximum duration, assuming that you don't waste any time after opening and that you land downwind. So, to be on the safe side, remove 500-1000ft from the opening altitude.
Knowing the duration of the flight D, the horizontal airspeed of your canopy H and the speed of the winds W, you can compute the distance travelled: T = D*(H + W), assuming that you're going downwind. For instance, with D=800 seconds (0.22 hour), H=14mph, W=20mph, T=0.22*(14+20) = 7.5 miles.
Again, the values are given as examples, and the result is the maximum distance. You might want to open closer to the DZ.
Have fun (and take warm clothes :-)
Come

[lazerq3 0]

Thanks for the input CRAZY........I'll work on those calculations...however I'm not worried about hitting the DZ cause I'll be leaving over it and landing wherever I end up!! (lots of open fields for miles!!!) The only concern I have is the GREAT SALT LAKE which is about 15 to 17 miles in the direction I need to go!! Cant go N,NE, or E cause of the mountains, cant go south cuase of the airforce base,(which is only 3 miles to the south), so I need to go W,SW .. anyway thatnks for the math!!
jason

[quade 4]

Maybe not exactly the way I'd do it, but essentially correct.
I'd first ask the DZO/manifest/pilot if they'd allow this to be done.
Then I'd look at all the potential airspace issues . It kind of looks like that's already been looked into so -- cool! Also, just a reminder, look at the ground issues too. I don't think I'd plan on doing any over swamps or forests just in case I had to chop or land short for some reason.
The 3:1 glide ratio is just an approximation of what you'd get in no-wind. Figuring out the actual glide ratio is going to be tough without a jump in no-wind conditions and even then it'll be a bit difficult without the aid of a GPS for the distance. You could use the 3:1 approximation but to be sure you're in the ballpark, you might want to back that off by maybe 20%.
Then, as already mentioned, you'll need to know the decent rate of your canopy with your wingloading. A rough estimate is probably 1000 feet per minute, but just by using a stopwatch on a hop-n-pop you can figure this out pretty easy. Pass 3000 feet and start the watch, don't do any radical turns or better yet, don't do any. When you pass 2000 stop the watch.
In the U.S., you should be able to get the winds aloft in increments of 3000 ft above sea level -- ask your pilot. Winds aloft are given with respect to true north and in knots, so you also need to compensate/convert for that.
After adding the glide ratio distance to the time aloft distance, I'd back off that distance an additional 20% just because winds aloft aren't all that accurate. Of course, this assumes you want to land somewhere in particular.
In some parts of the country, winds aloft can be wildly different from the ground winds or winds at some intermediate altitude. So, just averaging the winds at 2000 and ground level is not something I'd personally do.
Lastly, since you're planning on getting out over the home DZ and going for distance, communicate where you think you'll land (a particular school for instance) to your ground crew and make sure that everyone has a cell phone. I'd also have two pokcet GPS units; one for the ground crew and one for you. Then, when you land off, you can just give them the coordinates and they can find you. This is also not a bad safety idea in case you sprain you ankle behind a rock or something. It would totally suck to die of a sprained ankle, unable to walk and exposed to the elements.
In theory, you could use the GPS while under canopy to give yourself a good idea of how your doing on time and distance, but that could be a little akward.
quade
http://futurecam.com

[lazerq3 0]

Thanks Quade!!........
jason