Hovercraft FAQ

Hovercraft FAQ

The following page is by Alex Olshove

The original page is no longer available on the internet but used to be available from http://www.olshove.com/HoverHome/hoverfaq.html. For information about calculating lift system variables, see http://www.rqriley.com/hc-calc.html.
HOVERCRAFT FAQ (Frequently Asked Questions)
By: Alex Olshove
V. 1.33
LAST UPDATED October 2010.

This FAQ is meant to be used as general reference 
by those not familiar with the hovercraft.  If you reproduce this in 
any way, I only ask that you give me some credit (unless it's bad). 


1 This FAQ is completely sucky... how can I make repairs to it?
2 What is a hovercraft?
3 The Skirt
	3.1 What's the big deal about the skirt?
	3.2 What types of skirts are there?
		3.2.1  The bag skirt
		3.2.2  The segmented skirt
		3.2.3  The juped skirt
	3.3  Comparison between skirts.
4  The Engine
	4.1  How many engines does a hovercraft need?
	4.2  What types of engines can a hovercraft use?
5  Okay, a hovercraft sits on a cushion of air but where does the air 
come from?
	5.1  How many fans does a hovercraft use?  
		5.1.1  Single fan design
		5.1.2  Dual fan design
	5.2 What types of fans are there?
		5.2.1 Axial fans Ducted fans Propellers Propellers vs. Fans
		5.2.2 Centrifugal fans
6  How much does a hovercraft cost?
	6.1 What are some good sources for buying a hovercraft?
7  Where can I find plans to build a hovercraft?
8  Do you need a pilot license? Driver license? Any US states require 
9  Are there associations and conventions for hovercraft owners?
	9.1  Conventions
		9.1.1 U.S.A.
		9.1.2 France.
10  Are hovercraft allowed on public roadways?
11 What companies manufacture hovercraft?
	11.1  Australia
	11.2  England
	11.3  Canada
	11.4  Holland
	11.5  U.S.A.
12  Where can I get more information about hovercraft on the 
13  Can you recommend good hovercraft books to read?
14  Can you make a hovercraft stop and back-up?
	14.1  Reversible pitch fan
	14.2  Reverse bucket
	14.3  Transmission
	14.4  Puff ports
15  Can I insure my hovercraft?
16  Aren't hovercraft ‘handicapped’ when it comes to control
17  Do Hoverboards like in ‘Back to the Future’ really exist?
18  Where the heck to do I find 1/8” marine plywood!?!
>1. This FAQ is completely sucky... how can I make repairs to it?
 Just e-mail me at .  I'm not claiming to be an expert so 
there may very well be errors in this and I'll be happy to fix them 
or add more information if you want to set me straight. ;-)
>2. What's a hovercraft?
 I'm going to answer this question with a description of newer, 
popular hovercraft.  Perhaps I'll add a history lesson later with 
descriptions of peripheral jets, etc.
 A hovercraft is a vehicle which is suspended upon a cushion of air.  
The cushion of air is generated by a fan which is attached to an 
engine which is attached to the hovercraft.  The cushion of air is 
contained by a flexible sleeve called a 'skirt' that is attached 
around the perimeter of the craft to hold the air under the craft and 
thus upon an air cushion.  The craft is then propelled by whatever 
means is necessary to carry it forward.  A majority of craft simply 
utilize a ducted fan or a propeller attached to a small 2 or 4 cycle 
engine.  Be assured that pretty much every mode of propulsion known 
to man has already been tried from jet engines to sails.
 Control of a hovercraft is accomplished primarily through the use of 
rudders like the type used on aircraft.  The main difference would 
be, however, that hovercraft generally utilize many rudders rather 
than just one.  Another method of control is through 'puff ports' 
(see 13.1.4) or dual thrust fans where you would slow one down and 
speed up the other to turn in the direction desired. 
	>3.1. What's the big deal about the skirt?
 The skirt is one of the most important parts of a hovercraft as it is 
the part that allows the hovercraft to clear obstacles.  Generally 
speaking, the higher the skirt, the larger the obstacle that the 
craft will clear.  However, if the skirt is too tall, the craft will 
'slide off' the cushion and the cushion will deflate or the craft 
will become extremely unstable.  This is not a FAQ on hovercraft 
design so I won't go into this in any more detail.  On larger craft 
(> 1 or 2 tons) the skirt is made of heavy, rubberized fabric.  On 
smaller, recreational craft, the skirt is made of neoprene coated 
nylon that weighs >= 8 oz/sq. yd.
	>3.2. What types of skirts are there?
 There are several types of skirts but the most common are the bag 
skirt, the segmented skirt,  and the jupe skirt.
		>3.2.1.  The bag skirt:
 The bag skirt is basically just that... a bag.  The bag skirt should 
probably be called a tube skirt because it consists of a tube that 
encircles the perimeter of the craft.  The bag is inflated which 
serves to lift the craft off the ground and more importantly, to 
contain the air cushion.  There are two methods of inflating the bag 
skirt, the first being serial feed and the second being parallel 
feed.  The serial feed method requires that air be directed from the 
lift fan _through_ the skirt and then out into the cushion.  The 
parallel feed method requires that a certain amount of air be split 
off of the lift fan into the skirt (about 10%) and the rest  into the 
		>3.2.2.  The segmented skirt:
 The segmented skirt is also called a 'finger' skirt because it 
consists of several separate nylon segments that, when inflated, 
press together to form a shape that looks like fingers of a hand that 
are pressed tightly together (place your hand into a fist and then 
look at your knuckles).  Although much more complex to manufacture 
than a bag skirt, the segmented skirt offers much less resistance to 
obstacles and much more ease of repair when damaged since you only 
need to replace one or two damaged fingers instead of an entire 
skirt.  Segment skirted craft, however, are less stable than bag 
skirted craft (not necessarily a bad thing if you race hovercraft).
		>3.2.3.  The juped skirt:
 The jupe skirt (a.k.a. cell skirt)  consists of several cells that 
look like cones with their tops cut off and have their bases attached 
to the bottom of the craft.  When inflated, these cones readily 
support the weight of the craft upon a stable cushion.  A jupe 
skirted craft generally utilizes a minimum of 2 or 3 cells surrounded 
by a large jupe that encompasses the perimeter of the craft.  
Although a jupe skirted craft is very stable, it will experience 
difficulty when attempting to inflate the jupes on a rough terrain 
such a tall grass or deep gravel.  Jupe skirts also tend to scoop 
water in rough conditions and drag on grass.
	>3.3. Comparison Between Skirt Type (excerpt from 'Light 
Hovercraft Design' by Christopher Fitzgerald and Robert Wilson):
  					 Bag		     Segment        Jupe
 Cost                low            high           low
 Labor               low            high           medium
  smooth water       same           same           same
  Rough water        high           low            very high
  Mud                high           low            low
  Grass              high           low            medium high
  Ice                same           same           same
  smooth snow        medium         low            low
  rough snow         high           low            medium
 Reparability        hard           easy           hard
 Life                good           moderate       good
 Durability          good           poor           moderate
 Stability           good           poor           Excellent
 Plow in             same           same           same
 Roll ability for 
  turning            slight         excellent      none
 Dust and spray      poor           good           poor
 Colors available    limited        unlimited      limited
 Ease of attachment  moderate       easy           moderate hard
 Weight of skirt     low            moderate       low
 Hump performance    moderate       good           poor moderate
 High speed          good           moderate       moderate
 Bulkiness           poor           poor           good
 Appearance          moderate       good           moderate
 Bounce              poor           good           good
 Performance when
  damaged            moderate       good           poor
 Potential for
 development         good           good           good
 Over water rapid 
  take off ability 
  from long time 
  floating mode      poor           good           excellent
 Obstacle capability poor           good           poor
 Complexity          low            high           moderate
	>4.1. How many engines does a hovercraft need?
 With the exception of human powered craft, a hovercraft needs at 
least one engine.  With a conventional hovercraft, air needs to be 
supplied to lift (to make the cushion) and thrust (to propel the 
craft).  The supply of air to lift and thrust can be accomplished 
using only one engine  by either powering a single fan and then 
splitting an amount of air off to lift (about 33%) and the rest for 
thrust (called an 'integrated' system) or the one engine can be used 
to power separate lift and thrust fans.
 Most hovercraft, however, use a dual engine system where one large 
engine is used for thrust and another, smaller engine is dedicated to 
lift.  Unlike the integrated system, this allows the craft to remain 
hovering while the thrust engine is turned off.
 Larger, commercial craft may use as many as 6 or 8 engines for power 
of the lift and thrust systems.  Engines types range from diesel to 
gas turbine.
	>4.2.  What types of engines can a hovercraft use?
 A hovercraft can use (and probably has used) any type of engine you 
can think of.  The main point of concern about the engine to be used 
is weight.  Obviously a high weight to power ratio is bad for a craft 
that is supported by a cushion of air.  Although an air cushion can 
support a massive load, that load must still be moved and accelerated 
from a dead stop (and then stopped again when need be).  Also, drag 
becomes more imminent as the weight of the craft increases.  So, you 
must try to keep the engine light and powerful.  Currently, the 
engine with the best power to weight ratio is the 2-cycle engine 
which is the primary engine used for racing hovercraft.  
Unfortunately these things are _generally_ noisy and temperamental.  
Also, they generally require a gear, belt, or chain reduction system 
to match the fan or propeller they are powering.
 A large majority of hovercraft utilize the heavier, but quieter, 4-
stroke engines.  Although these engines put out less power than a 
similarly sized 2-stroke engine, they are much quieter, don't require 
a special fuel-oil mix, and sometimes don't require a gear-down 
 Large, military or commercial craft will sometimes utilize jet 
turbine engines that put out thousands of horse power as well as 
large diesel engines.
>5. Okay, a hovercraft sits on a cushion of air but where does the 
air come from?
 The answer is 'fans'.  Fans are a very important part of a hovercraft 
whose primary purpose is to inflate the cushion contained within the 
skirt beneath the craft as well as to provide thrust with which to 
propel the craft forward.  For all intents and purposes, 'fan' in 
this text will be used to describe any air moving device.
	>5.1. How many fans does a hovercraft use?
 A hovercraft can use as many fans as the designer wishes.  In fact, 
the larger military and commercial hovercraft like the Bell Aerospace 
AALC Jeff (B) uses six lift fans and two thrust fans.  In the 
recreational hovercrafting world, however, most craft function on two 
basic designs. The single fan or the dual fan design.
		>5.1.1.  Single fan design
 In the single fan design, one engine powers one fan (or propeller).  
Most of the air generated by this single fan is directed rearward as 
thrust while a moderate percentage of the air (c. 33%) generated is 
split off and thrust below to charge the air cushion contained by the 
		>5.1.2.  Dual fan design
 In the dual fan design,  one or two engines are used to power two, 
separate fans.  One of the fans is dedicated to the generation of air 
for the maintenance of the air cushion beneath the craft while the 
other is dedicated to the generation of air to provide forward 
momentum for the craft.  Typically, this configuration utilizes two 
separate engines but occasionally, you will see a system devised 
which uses only one engine to power both fans.  This often proves to 
be a more daunting task than using two separate engines as the 
mechanics involved may become very complex.  After all, you need to 
provide a constant speed to the lift fan while allowing the thrust 
fan's speed to be moderated. If not, the basic advantage of using two 
fans is lost.
	>5.2.  What types of fans are there?
 There are several types of fans that may be used  but the two main 
types of fans are axial fans and centrifugal fans.
		>5.2.1  Axial fans
 Axial fans are those that propel air parallel to their axis.  Of the 
axial type of fan, there are propellers and ducted fans.
			> Ducted fans
 Ducted fans typically utilize several blades that are generally wide 
at the tip and  taper towards the base.  A ducted fan may contain as 
few as 3 blades and as many as a dozen or more.  These fans need to 
be contained within a duct to realize their peak performance.  Some 
advantages of ducted fans include the ability to mount reversing 
mechanisms such as reverse buckets which direct air forwards when 
placed in the column of air generated by the fan.  Also, ducted fans 
are generally of a smaller diameter than propellers which can allow 
several fans to be placed side by side thus allowing for better 
control of the craft (speed one up and slow one down and the craft 
turns).  One more major benefit that comes from using fans is that 
fans are readily available from ventilation companies.  Ducted fans 
can be used to provide either lift or thrust.
			> Propellers
 Propellers typically utilize between 2 and 5 blades that are quite a 
bit longer than those used on ducted fans.  Although propellers are 
generally more efficient (and safe!) when placed in a duct, ducting 
is not a necessity as propellers will function well in open air.  
Propellers must be replaced if damaged by debris whereas a blade is 
replaceable on a ducted fan.  Propellers are generally noisier than 
ducted fans.  Propellers can be used to provide either lift or 

			>  Propellers vs. Fans.  (Note: This was 
taken from James Perozzo’s ‘Hovercrafting as a Hobby’ and is best 
viewed with Courier 10 font.)
    More thrust/HP		No blade edging
    Less costly		More costly
    Noisy			Quiet
    Rotate fast		Slow Rotation
    Edge blades avail.	Less blade erosion
    Large Diameter		Smaller diameter
    Must have a guard	Duct is also a guard
    8’ and more diam.	Only to c. 48” diam.
    Fast throttle resp.	Slow throttle resp.
    Replace whole prop.	Replace indiv. blade 
		>5.2.2.  Centrifugal fans
 Centrifugal fans are those that propel air perpendicular to their 
axis.  That is, they draw air in the center and 'fling' it out the 
side similar to the type used in hair dryers.  This type of fan is 
generally limited to use as a lift fan due to their orientation and 
relative bulkiness although some craft have been built that use 
centrifugal fans exclusively.
>6.  How much does a hovercraft cost?
 Depends on several factors.  A hovercraft could be build for less 
than $300 if you don't mind that it may only support 100 lbs and only 
goes 5 MPH.  However, if you need a craft that will support 2 adults 
over water at around 30 MPH, then you will probably spend in the 
neighborhood of $5000 for a pre-manufactured recreational craft.  If 
you can stand something that's used, you can get a good deal for 
between $1000 and $5000 for the same craft which will probably get 
you a trailer as well.  If you're handy with a saw and screwdriver 
then you could build one for less than $1000 or as much as you want 
to spend.  All in all, the cost boils down to the materials used to 
manufacture the craft (fiberglass or plywood?), the time spent, the 
engine(s) (Rotax 503 or B&S 12 HP?), the fan(s), the skirt (bag or 
segmented?), and the gadgetry (Radio? electronic actuators? 
	>6.1. What are some good sources for buying a hovercraft?
 The HoverClub of America's bi-monthly publication called 'The 
HoverNews' lists several good deals in the classifieds section in the 
back.  Also, there are a few hovercraft related pages on the Web that 
have a classifieds section.  You can also order a brochure directly 
from the manufacturers listed below.
>7. Where can I find plans for building a hovercraft?
 Why not design your own?  If you're not feeling that confident, then 
try the dealers listed below: 
 Sevtec Inc.
 PO Box 846
 Monroe, WA  98272.
 Scout  ($29)
 Vanguard ($44)
 Prospector ($48)
 Explorer ($62)
 Mariner ($92)
 Universal Hovercraft
 3rd Street Box #281w
 Cordova, IL 61242
 Phone / Fax (309) 654-2588
 Complete Catalog $2.00
 Too many plans to list
 Databoat International, LTD.
 PO Box 1073, 8609 Fissile Lane
 Whistler, BC Canada V0N 1B0
 Neoteric Neova 4 ($143.50)
 Robert Q. Riley Enterprises
 Box 12294
 Scottsdale, AZ   85267-2294
 Phone: (602) 951-9407
 Tri Flyer ($45)
 Pegasus ($35)
>8. Do you need a pilot license? Driver license? Any US states 
require licenses?
>9. Are there associations and conventions for hovercraft owners?
 Yes, here is a list of Clubs followed by some annual conventions.
	>9.1.  Clubs
 Australian Hovercraft Federation
 Michael Nell
 17 Fegen St.,
 Huskisson, NSW 2540, Australia
 Email: nell@mpx.com.au
 Title of Publication: Australian Hovercraft News
 Frequency of Distrbiution: Quarterly
 Cost of subscription: Australia AUS$20.00; USA US$25.00
 Contact: Tim pryor, Editor, Australian Hovercraft News [tpryor@mail.fairfax.com.au].
 38 Barnes Road, Frenchs Forest, New South Wales 2086, Australia
 Hovercraft Club of Canada
 10 Gold Crescent
 Russell, Ontario
 Tel / Fax: (613) 445-3139 
 Bob Rennick  
 Title of publication: 'Hovercraft Club of Canada Newsletter'
 Frequency of distribution: Four times a year
 Cost of subscription: Membership in the club ($15/yr)
 Hoverclub of America
 PO Box 908
 Foley, AL  36536-0908
 Phone: (334) 943-3279
 Title of publication:  'HoverNews'
 Frequency of distribution: Every two months
 Cost of subscription: Membership in the club ($30/yr).
 Hoverclub of South Africa
 5 Marais Street
 Somerset West 7130
 Title of publication:
 Frequency of distribution:
 Cost of subscription:
 Belgian Hoverclub
 Blvd St. Michel 78 1040
 Title of publication:
 Frequency of distribution:
 Cost of subscription:
 Title of publication:  "POTIN d'AEROS"
 Frequency of distribution: bi-monthly (once every two months)
 Cost of subscription: 12 (Francs?)
 Hoverclub von Deutschland
 Lechfeld Str. 2
 Title of publication:
 Frequency of distribution:
 Cost of subscription:
 Hoverclub of Great Britain
 Secretary: Mrs Brenda Kemp 
 Long Acre, Bingham, Notts, NG13 8BG 
 Title of publication:  Light Hovercraft
 Frequency of distribution: 
 Cost of subscription:
 Editorial contact: Jeremy Kemp 
 Long Acre, Bingham, 
 Nottingham, NG13 8BG 
 The Netherlands Hovercraft Club 
 Uiterdijksehof 5, 
 JK Nederhorst den Berg 
 Title of publication: Hovercraft Sportnieuws
 Frequency of distribution:
 Cost of subscription:
 Japanese Hovercraft Association
 C/o SOREX Co. Ltd.
 Kumenan-cho, Kume-Gun
 OKAYAMA-KEN, 709-36
 Title of publication:
 Frequency of distribution:
 Cost of subscription:
 Hovercraft Club of New Zealand
 David Van Bysterveldt 
 Robinson Rd, 
 4, Paeroa 
 Phone 64-7-862-4793 
 Title of publication: Hover News
 Frequency of distribution:
 Cost of subscription:
 Wellington and Wairarapa (New Zealand) Hover Club
 Kerry Workman
 Harvard Grove
 Totara Park
 New Zealand
 Phone: (04) 5267655
 Swedish Hoverclub
 Ollonvaegen 17
 Title of publication: Hover News
 Frequency of distribution:
 Cost of subscription:

	> 9.2. Annual Events
 There are many annual events around the world.  Here are some of them 
listed by country.  For more specific information, visit 
http://www.hoverclubofamerica.org/events.html courtesy of the 
Hoverclub of America.
 		>9.2.1. U.S.A.
 		What: West Coast Hover-In and Cruise
 		When: July
 		Where: Long View, Washington
 		What: The U.S. National Cruise on the Wisconsin River
 		When: August
 		Where: Muscoda, Wisconsin
 		What: Scioto River Hover-In & Cruise
 		When: August
 		Where: Chillicothe, Ohio
 		What: Tennessee Hover-in
 		When: October
 		Where: Big Spring, Tennessee
 		What: Texas Hover-In
 		When: October
 		Where: Dallas/Ft.Worth Texas
 		What: 23rd National Annual Hoverally
 		When: June 12,13, & 14, 1998
 		Where: Troy, Ohio
 		>9.2.2.  France
 		What: The World Hovercraft Championship
 		When: August
 		Where: Luçon in the Vendée, France
>10. Are hovercraft allowed on public roadways?
 Nope.  And you probably wouldn't get very far if they were since most 
roads are 'humped' up in the middle to allow for water run-off.  
Unfortunately, this also causes air cushion vehicles to slide off to 
the side of the road since there is no friction to hold 'em on there.  
If you're a skilled driver, then you can counteract the sliding 
affect by directing the nose of the craft towards the center of the 
road and 'crab' sideways like you would during heavy wind. 
>11. What companies manufacture hovercraft?
 The companies listed below are categorized by country.
	>11.1.  Australia
 Airlift Supercraft (Aust) Pty.Ltd.
 Olsen Avenue
 ASHMORE, 4214
 Phone: Australia 07 5527 8111 
 Fax: Australia 07 5527 8016
 AS 400 Thriller
 AS 560 Hoverflyer
 AS 560U HoverUte
 AS 600C Mustang
 AS 600A Mustang Ambulance
 AS 8900 Pioneer
 AS 10600 Pioneer L(ong)
 AS 1200 Challenger
 TURBO Hovercraft Pty. Ltd.
 Vortex Hovercraft Pty. Ltd.
 Turbo 235 Superwedge
225 Wedge
Vortex 245
Turbo 265 Super
Turbo 265 Hyper
Revolutionary Technology
11 Mulberry Court
Victoria, Australia, 3095
(Owen Ellis designer of Rocket)
Rocket (seen by many at the last world championships)

	>11.2. England
 Pegasus Aviation
 Elm Tree Park
 Manton, Marlborough, Wiltshire, SN8 1PS
 Tel. + 44 (0)1672 861578
 FAX. + 44 (0)1672 861550 
 Cyclone PRIMO
 Bill Baker Vehicles
 Eagle Hovercraft
 Ingles Hovercraft Associates Ltd.
 Ingles Manor
 Castle Hill Avenue
 Folkestone, Kent CT20 2TN
 River Rover
	>11.3. Canada
 AeroTour Canada
 1279 boul. Hurtubise
 Gatineau, Quebec, J8P 7C2
 Tel.: (613) 762-3167
 Voice and fax: (819) 669-8454

 Canair Hovercraft Inc.
 O. Box 478
 Carleton Place, Ontario
 K7C 3P5
 Telephone: (613) 257-8332
 Facsimile: (613) 257-7948 
 Canair 504L
 Surface Effect Boats (S.E.B.) Enterprises Inc.
 AirCat 7
	>11.4.  Holland
 Hovertrans B.V.
 Keizersveer 9
 The Netherlands
 Telephone: +31 1622-3062
 Tel/Fax: +31 1622-3075
 HP Design 
 Uiterdijksehof 5 
 JK Nederhorst den Berg 
	>11.5.  U.S.A.
 Hovercraft America
 N114 W18605 Clinton Dr.
 Germantown, WI 52033
 Phone: 414.253.9979
 FAX: 414.253.9033
 Hovercraft Concepts
 13910 SW 139 Court
 Miami, FL 33186
 FAX: 305/256-8698
 Contact: William Flett
 SA 580
 Aerocruiser SA 1100 (price: $12,995)
 Starcraft RX2000
 GPL Enterprises
 Contact: Gary Lutke 
 Tangelo Terrace #A13 
 Delray Beach, FL 33444 
 Phone: (407) 274-2247 or (800) 541-7228
 Fax: (407) 276-4159 
 Air Commander
 Neoteric Hovercraft Inc.
 Tippecanoe Street, Dept.. 12
 Terre Haute, IN  47807-2394
 Telephone: (800) 285-3761 
 Alternate Phone: (812) 234-3217 
 Fax Phone: (812) 234-3217 
 Oregon Hovercraft
 27612 Crow Rd.
 Eugene, OR 97402
 Telephone: (541) 485-0588
 Sevtec Inc.
 PO Box 846
 Monroe, WA  98272.
 Hovertechnics Inc
 Contact: Hugh B. Firminger 
 Box 257 
 St. Joseph, MI 49085 
 Phone:(616) 925-0025 
 Fax: (616) 925-6940 
 Weber Hovercrafts
 28728 Crabtree Corner Road
 Cuba City WI 53807
 Phone: (608) 744-3678: Verdon
 Fax: (608) 759-5704: Vernon
 StarCruiser 1-4
 Price: $3400 +
 SCAT Hovercraft of Washington
 PO Box 4838
 Federal Way, WA  98063
 voice (206) 838-5005 or (888) NEW-SCAT
 New Mexico Scat
 P O Box 90575
 Albuquerque  NM  87199
 Dan Morris
 Phone: 505-828-2273
 St. Louis Hovercraft Rides Inc.
 P.O. Box 73
 Chesterfield, MO  63006
 Michael Murphy (MURHOVER@aol.com)

>12. Where can I get more information about hovercraft on the 
 When I first started the Hovercraft Homepage, there was no, none, 
zip, zero, nada information about hovercraft on the Internet.  Now 
there are hundreds of web pages to access.  If you're too lazy to do 
an Alta Vista search, here are what I consider to be the main pages:
 http://www.olshove.com/HoverHome My Hovercraft Homepage.
 http://www.hovercraftersresource.com/  Kelly Jernigan's Hovercraft Resource.

 http://members.aol.com/sevtec/sev/skmr.html Barry Palmer's Sevtec 
 http://www.hoverclubofamerica.org/ The HoverClub of America's 
Official Homepage.
 http://www-personal.umich.edu/~untitled/hover.html HoverTechnic's 
 http://www.ozemail.com.au/~ahf/index.html The Australian Hovercraft 
Federation Page.
 http://www.ils.nwu.edu/~eric/hover.html Eric Goldstein's page. 
 http://www.innotts.co.uk/~pault/hcgb.htm The Hoverclub of Great 
Britain Homepage.
 http://www.hovercraft.com  Universal Hovercraft.
 http://www.peaceregion.com/hover/ The Hovercraft Club of Canada 
 There is now one newsgroup relating to hovercraft called 
alt.rec.hovercraft.  If you don't see it on your local news server 
then please e-mail root@ (root@xoom.com or root@netcom.com, 
etc) and request that they start carrying alt.rec.hovercraft on your 
news server.
 An easy way to read and post to alt.rec.hovercraft is through a 
service called DejaNews.  You can get to this service via your web 
browser by entering http://www.dejanews.com as the location.  When 
you get there, you can simply enter ‘alt.rec.hovercraft’ in the edit 
box marked ‘Type a specific question or topic:’.
 I have the capability to start a mailing list but I want to see how 
the news group does for awhile before I consider maintaining such a 
pain in the hoo-ha.

>13. Can you recommend good hovercraft books to read?
 Sure thing.  In fact, these were the primary sources for this FAQ 
(other than from my noggin that is). ;-)
 Title:  Hovercrafting As a Hobby
 Author: James Perozzo
 Subject:  All aspects of hovercraft design for recreational use.
 Available From: Twin Peaks Publishing; 30455 Kent-Blk Diamond Rd., 
Auburn, WA 98092. (253) 631-7347.
 NOTE: The author has passed away and this book is out of print.  If 
 you can get a copy, it’s a good book for beginner to intermediate.
 Title:  Jane's Surface Skimmers
 Author: Jane's USA
 Subject:  General hovercraft reference.  Lists darn near everything 
 ever built.
 Available From: http://www.janes.com/.
 Your best bet for getting your hands on one of these rather expensive 
references is to search for a used one through a book exchange.
 Title:  Light Hovercraft Design
 Author(s): Christopher Fitzgerald and Robert Wilson
 Subject:  General hovercraft design reference.
 Available From: The Hoverclub of America.  See above for contact 
>14. Can you make a hovercraft stop and back-up?
 Yes, although it requires some mechanical wizardry since no part of 
the craft is in contact with the ground.  This is generally 
accomplished via reversible pitch fan, 'reverse bucket', 
transmission, or 'puff ports'.
	>14.1.  Reversible pitch fan
 A reversible pitch fan (or propeller) is a fan that allows the 
operator to physically reverse the pitch of the fan blades thus 
reversing the flow of air forward thus slowing and/or reversing the 
direction of the craft.  These are mechanically complex and are not 
useful in a craft of single fan design (see 4.1.1.a) since the 
reversing of the airflow would essentially create a vacuum in the 
cushion and suck the craft to the ground.
	>14.2.  Reverse bucket
 A reverse bucket is placed, mechanically, directly rearward of the 
thrust fan to redirect it's airflow forward via a curved surface when 
the operator wishes to slow the craft or stop.  Although this method 
is much simpler than a reversible pitch fan, the bucket adds weight 
to the rear of the craft in addition to the engine, duct, fan, and 
rudders.  Also, reverse buckets are only useful with smaller diameter 
	>14.3.  Transmission
 A transmission is sometimes as complex a solution as a reversible 
pitch fan.  As in an automobile, a transmission reverses the rotation 
of the fan and is attached to the driveline between then engine and 
the fan.  A transmission may utilize gears as in an automobile or 
belts as in a 'mule drive'.
	>14.4.  Puff ports
 Puff ports are apertures through which air is redirected from the 
lift or thrust system to the front or sides of a hovercraft.  When a 
puff port is opened, the air is allowed to flow out of the craft in 
whatever direction the operator desires.  Realistically, puff ports 
are only useful at slow speeds since they often lack the ability to 
pass air at a sufficient velocity to counteract a craft with much 
momentum and are used primarily for low speed maneuvering.
>15.  Can I insure my hovercraft?
 Currently, insurance for hovercrafts is very difficult to obtain (in 
the USA anyway).  Most insurance companies don't even know what a 
hovercraft is but may insure your craft as a boat
>16.  Aren't hovercraft  ‘handicapped’ when it comes to control 
 Nope, we prefer to see those as "limitations of frictionless motion".  
It could as easily be said that automobiles suffer from the handicap 
of not being able to move over water or that boats suffer the 
handicap of not being able to transition to land travel.  The primary 
advantage of the hovercraft is that you can fly them over any 
relatively flat surface on land, snow, mud, water, swamp, peat bog, 
river, etc.  They are being used more and more often for rescues, 
ferrys, and general grins (_big_ grins).
 Advances are gradually being made in control.  We've learned, for 
instance, that a tighter, more controlled turn at speed can be made 
by tilting the hovercraft to one side and banking it through a turn. 
This can be accomplished by operator weight shift, elevons, or 
cushion control mechanisms.  The resulting control starts to approach 
that of your average speed boat on full plane and exceeds that of 
your basic automobile on an icy highway. ;-)
 Braking is accomplished fairly effectively through the use of thrust 
reversing mechanisms such as reversible pitch propellers, and reverse 
True, hovercraft don't offer the best response times for braking and 
steering as water plows (boats) and automobiles but owners/operators 
of hovercraft would agree that the advantages of hovercraft travel 
outweigh the disadvantages which, by the way, are adjusted to as the 
operator gains experience.

>17. Do Hoverboards like in ‘Back to the Future’ really exist?
Figure it this way.  An axial fan puts out only so much lift 
per horsepower.  In hovercraft terms this is measured in pounds per 
square foot.  A good lift system will produce 10 lbs per sq. ft.  
Multiply the the area of the hovercraft by the lbs-sq-ft for a rough 
idea if it will work or not.  How big is the hoverboard?  1' x 4' ?  
That is 4 square feet.  With a good lift system you will have 40 lbs 
of lift total.  Now, how much do you weigh?

Note:  This explanation was graciously provided by Dave Galka who is 
the editor of HoverNews for the Hovercraft Club of America.  In 
summary, a 1’ x 4’ board is capable of supporting about 40 lbs.  
Unfortunately, most humans weigh much more than this.  Sorry, but 
hoverboards will not be a possibility unless a seriously powerful 
power source can be devised.  Preferably one that can supply at least 
40 lbs per square foot and still fit within the confines of 1’ x 4’.

>18. Where the heck to do I find 1/8” marine plywood!?!

Okoume is a fairly common mahogany 3-ply marine plywood available 
from numerous sources. It is light, bends easily and is moderately 
durable.  Below are some suppliers:

M.L. Condon Co., Inc.
260 Ferris Ave.
White Plains, NY  10603
914-946-3779 (fax)
Marine grade okoume - 3 mil, 4x8 $40 / sheet

Edensaw Woods, Ltd.
PortTownsend, WA
Marine grade okoume - 3 mil, 4x8 $37 / sheet

Boulter Plywood Corp.
24 Broadway, Dept WB
Somerville, MA  02145
617-666-8956 (fax)
Marine grade okoume - 3 mil, 4x8 $39 / sheet

Harbor Supply
1401 Russell Street
Baltimore, MD  21230
410-752-0739 (fax)
Exterior grade okoume - 3 mil, 4x8 $24.68 / sheet
Marine grade okoume - 3 mil 4x8 $53.20 / sheet