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teamhypoxia

Effects of altitude on swooping

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February's Skydiving magazine mentions the largest swoop pond in the world to be built at Mile Hi Skydiving in Colorado. This DZ has a field elevation of approximately 5000ft msl. I'm curious as to opinions on the effects of altitude on swooping. From my purely unscientific observations, it feels like I swoop for a longer period of time at sea level, but at a slower speed across the ground. Will the thinner air provide more speed but less lift? Will the effects cancel each other out in terms of distance? Will the optimum wing loading on a certain canopy change? I bet we could see speed records broken at this elevation, but what about distance? Thoughts?

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As a MHSD jumper, it is my experience/impression that jumping here at 5000' MSL results in fast swoop speeds. But this does not seem to translate into super long swoops due to the thin air and high density altitude conditions (don't get me wrong, I can swoop 200-300 feet who knows maybe even further now that I'm on a new x-braced wing). But I can tell you though that if you do jump here and do swoop at altitude, it is very important to know how to complete your flare. Of course you do jump here in CO, so you should already know this. ;)


Try not to worry about the things you have no control over

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From a purely scientific point of view, the higher altitude will mean higher speeds, but at the same time less lift will be produced at any one speed. I'm not sure on how they will interact, but I would guess sea level swooping (purely from a distance standpoint) would be best. Combine this with a hot day at mile hi and you'll be in for a ride, as these factors are based on air density, which decreases with temperature and is obviously already low up there. I recall having to use 2/3 the runway at Colorado Springs in a 172 on a 100 degree day.



I got a strong urge to fly, but I got no where to fly to. -PF

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Behold young paduwon learners... The swoop is longer not...

So after that cheesey Yoda Annecdote, The swoops up here are really not that much longer than down at sealevel. It's just easier to build up speed for your entry. Conversly your canopy will quit flying at a slightly higher airspeed, so shutting them down can be a little tricky.

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I am glad someone asked the question. This is something that has been discussed at length by those that are organizing the competitions to be held at Mile Hi this year. (more details to follow soon) I have talked to some of the best canopy pilots in the world, and the only consistent answer i get is "we will find out". A competition at the end of the year will offer a large cash prize to anyone that can break the world distance record. Stay tuned, some very exciting anouncements about this pond and events to be held here this year are to be released soonB|

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Hi Baart,

I don't know. Airspeed equals lift - and we have a lot of airspeed. I know sprinters run faster at altitude, and golf balls travel further...

I must confess I wasn't really impressed by the distance covered by those who appeared to know what they were doing in Eloy, but don't know what they were trying to achieve, or if they were even trying. They did lots of clever tricks I could never manage, but never covered much ground. The (senior) landing area in Eloy is very short. We have jumpers (younger, braver, jumping FX and VX 94's) who seem to cover more ground here but don't do tricks.

I think speed = distance. I think that the air even in Eloy and Elsinore felt like flying in glue, and I don't really know how to do that.

Although I swoop - I'm not really trying and I'm not jumping a swoop canopy or even a high wing loading. I just want to stand them up so I don't tear my S3, or my Pantz.

What I do know is that a LOT of people fall down when it gets hot here. People with 400 - 500 skydives on moderately loaded canopies get caught out around lunch time in Summer and get really dirty.

Flying at altitude is a skill that needs to be developed. Patrick De Gayardon discovered that in Dec 1992 at Mmabatho (surface Elevation about 3500 ft AMSL - about 100+ Deg F) when he flew, and flew, and flew until he was eventually stopped by a barbwire topped chain link fence. I think that was back in the days of the Blue Track. He certainly expected to fly less far than he did - but then I don't think that swooping was his strong point.

Time will tell.

t
It's the year of the Pig.

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When you start doing freestyley, your distance suffers as you are distorting the wing greatly.



Spizzarko is absolutely right and not only that, the tricks that tonto is talking about in eloy were things like blindman supermans and things that require a large amount of dragging feet. this definately kills a lot of air speed and with that , distance

maybe there is a point where as you go too high the air becomes too thin and the distance is affected negatively although the speed is still high.

could it be that there is a point where the swoops will be furthest. right air density/ altitude and perfect execution of turn. somewhere higher than sea level and lower than some of those really high altitude DZs

i wonder. we should go on a mission and swoop all the dropzones in the world at all the different altitudes and see if one really consistently produces higher results.

who's with me!

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A lot of people don't really realize how a little bit of drag will adversly affect your swoops. Jumpsuit type, body position, chest strap, and slider collapsing are all HUGE things when it comes to going to distance. When you start to drag toes or feet, it really kills a lot of airspeed. When doing freestyley, there is a lot of twisting in the harnes, that causes the canopy to turn, and you have to correct with a toggle or riser input. This causes drag, and shortens your distance.

As far as the happy medium, I believe that swooping at sea level is your best bet for the longest swoops. It comes down to loading the canopy and how your distribute your power gained in the turn into your swoop, not a Mean Sea Level MSL or Density Altitude DA figure. The loading along with canopy design ( let's not forget technique, jumpsuit, body position) regulates what speed you can achieve with your canopy.

Every canopy actually has a Terminal Velocity. This TV is not achieved by constantly muscling your fronts down. With fronts you are going to go fast, but if you continued to hold the same input you would actually slow down. This is because you are introducing drag with the distortion of the canopy.

The fastest a canopy is going to go (TV) is actually in the full flight configuation. This happens after you do your front riser input and you put the canopy into full flight.

Try this up high... Do your usual front riser input, and then put the canopy back into full flight, and listen to the wind then entire time. You will find out that your canopy is going to speed up quite a bit after the front riser input. With this in mind bump up your turn to approach altitude.

The ammount of speed you carry into your swoop roughly determines how much distance you are going to get in that swoop ( body position, jumpsuit and being smooth helps out quite a bit too, but not as much as the amount of speed you put into it).

As far as the DA and MSL thing goes, these items will only adversly effect your swoop distance. I my opinion, if you loaded up a slightly bigger canopy (111-120) up to it's optimal wingloading, and did an optimal turn, on a cold, calm, and dry day down at sea level, this would give you optimal conditions for some optimal swoops.

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this would give you optimal conditions for some optimal swoops.

you aren't fooling anyone with all those big words spizz!!! we all know you have no clue what you're talkin about
History does not long entrust the care of freedom to the weak or the timid.
--Dwight D. Eisenhower

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when i was down at sea level i noticed a definite increase in the distance of my swoops(they were only straight in double fronts though so take it for what its worth) and obivously the bottom end flare was much better at slower speeds.
History does not long entrust the care of freedom to the weak or the timid.
--Dwight D. Eisenhower

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I've done a fair amount of swooping in Albuquerque, which is at 5000 ft., as well as Perris and Eloy (~1500 ft.), and a little bit at sea level. My opinion is that obviously, you are faster the higher the density altitude. As far as distance goes, I think it depends to some degree on the wingloading you have on your particular canopy. What I find is that if I am at or above maximum efficiency, my swoops get shorter with higher density altitude. If I am below max efficiency, the distance doesn't seem to change much.

Just my .02


"Holy s*** that was f***in' cold!"

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As far as distance goes, I think it depends to some degree on the wingloading you have on your particular canopy.



I think you've got something there. I've got a few jumps on a Stilleto, and I've noticed that their performance drops RIGHT off when loaded above 1.8. Lower loaded canopies, as low as 1.4 ppsft get really looong swoops up here - while at the coast they just stop.

t
It's the year of the Pig.

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Anyone want to change their answer before we see some concrete evidence? ;)



I think that after jumping in Colorado, everyone is just going to be so confused by density altitudes, horizontal and vertical vectors, lift, drag, wind, velocity, distance, setup points, entry gates, verticals, egos, water, dirt, beer, and trailer rides that they all forget how to swoop and the poles of the canopy piloting world are going to reverse and the "cool new thing" will be landing on an accuracy tuffet with a parafoil 252 wearing a bright red, practically painted-on skin-tight style suit. Oh ya, and I heard the Wonderhog container is going to make a comeback too! :P

We'll see how accurate my hypothesis is after the comp. :)


Cheers,
Travis

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Not sure how the average jumper is going to feel about our fast landings here in CO, but the swoopers like it and have already spoken about either returning as a visitor or better yet ... moving here. I grew up jumping in the thin air of CO and liked it. Now more people are getting to know why we like it here as well. B|


Try not to worry about the things you have no control over

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Airplane and glider pilots have long known that landing distances increase with altitude.

I'm not sure what the big mystery is, lift is related to indicated airspeed, which will remain constant. It is the TRUE airspeed that is increased with altitude resulting in higher groundspeeds and longer distances covered.

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I don't know. Airspeed equals lift - and we have a lot of airspeed. I know sprinters run faster at altitude, and golf balls travel further...



think terminal lift. same as terminal velocity.:)

i said this before,. or something close to it, the wing is going to seek its lift point. at points where there is less drag, the speed is going to be faster.

MILE HIGH SKYDIVING!!!!= KICK ASS SWOOPS!!!!

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Scott Roberts - not sure of the exact number, but over 600



i think scotts run was 610.

but, i asked to go before these guys because i KNEW i was going to get a world record, i had already done it. i knew iu was going to get beat. but it is a nice feeling that you hold the distance world record for those 3 minutes...

jay mo!!! nice job... no shit... nice job....

but im comin to get you, so make sure your factory steps up the bar.!!!:| or you might find yourself in second place!!!!;):)
i love ya man........ and thanks for the tape, i would have broken my heal without it!:P


game on!!!!! lets fuckin see some kick ass swoopin!!!!;)

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