Can a Single Wide Skirt Design Improve Wheelchair Access on a Hovercraft?

[matt5]

I am currently working with a foundation whose goal is to modify a hovercraft so that a wheelchair restricted person has easy access to the main deck of the craft.
A challenge our team is facing in the modification of this craft is a suitable method of allowing access to the craft by a wheelchair. The craft hull is made of approx 1/4" thick fiberglass and currently has a finger type skirt attached to it.
My idea is to modify the front panel so that it is removable, to allow ramp access to the deck. This however, creates air flow and pressure issues. Would it be possible to remove the five separate finger sections at the front and replace them with a single, wider section of skirt so that the air flowing into this section would come from the holes on either side of the front panel? The front panel section could then be sealed off so that no air is lost through this front section.

An additional ramp could then be used to pull the wheelchair backwards upwards to the height of the side of the craft, and then back down to the deck height. I envisioned that the front panels could be separated and could slot into slots of some kind when the craft is in use.

Any help is much appreciated

 

[Danger]

Welcome to PF, Matt.
How big is this machine? If it's of significant size, I would think that building a specialized loading mechanism would be less troublesome than modifying the skirt.

 

[matt5]

Thanks for the reply. As can be seen by the photos, craft is about 5m by 1.5 m. Currently a small gantry is used to lift users into place but a less invasive method is being attempted.

http://img259.imageshack.us/img259/3018/copyofp1010235.th.jpg

http://img713.imageshack.us/img713/7170/p1011184.th.jpg

http://img823.imageshack.us/img823/3876/p1011193.th.jpg

 

[Danger]

Hmmm...
Your first picture gave me a decent idea, and the second one shot it down.
As to your first question, I think that I understand what you are proposing and see no reason why it wouldn't work. The only drawbacks would be a lessening of flexibility and the "damage control" factor, both of which are primary reasons for using finger skirts in the first place.
I'm afraid that I don't follow your last sentence regarding the slots, so a bit of clarification would be helpful.

 

[matt5]

The craft is for use solely on water, and will only come on to sand/short grass to transfer passengers, so damage control should not be a huge issue should it? By the slots i mean making the vertical panel at the front of where the passengers are located, and the angled front panel of the craft (Which is removed in the last picture) slide on rails (Like a sliding door, but it shouldn't need rollers i wouldn't imagine?) for easy removal.

Once all passengers are in the craft, the front panel would slide downwards into place, and be locked in by the vertical panel which is then added. This could then be latched down somehow.

As far as the skirt goes, do you see any reason why their wouldn't be adequate airflow through the front, larger section of skirt?

Thanks for your help so far

 

[Danger]

Gotcha. Given those constraints, damage control shouldn't be an issue. That pretty much enters the scene when you are traversing driftwood, sharp rocks, stumps, etc..
I would recommend, for your sliding parts, that you frame them with either wood or metal. Fibreglass tends to bind. If wood is used, coat it with some decent paste wax. Should you choose aluminum or steel, give it a decent dose of lithium grease or moly-disulfide. Either one is slicker than owl snot on a brass doorknob, and highly resistant to water.
I see no problem with airflow, other than perhaps a very minor pressure drop which should easily be overcome by throttle alone.