TOPIC NUMBER:  A02-218

TITLE:  Development of Ballistic Resistant Airless 20 Inch Wheels for the Interim Armored Vehicle (IAV) 
and Future Combat Systems (FCS)

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Q: 1) What are the ideal tire dimensions that are acceptable - overall
diameter, overall width, static loaded radius, etc. of this 20 inch tire?
  2) How many tires per vehicle?
  3) Max load per tire? Is the load requirement uniform in every position
or are there differences in load requirements depending on the tire position
on the vehicle?
  4) Are there any weight limits per tire and wheel assembly?
  5) Assuming that there are 6 tires on a vehicle, please advise what the
speed and distance will be required if:
	1 tire is shot out?
	2 tires are shot out on the same side of the vehicle?
	3 tires are shot out on the same side of the vehicle?
	Or if all 6 tires are shot out? 

A: 1) Overall diameter is 44 inches, width is 12.2 inches, loaded 
radius of 20.7 inches.
  2) Eight wheels.
  3) Please go to Michelin's website for load and pressure, link as 
follows:  http://truckus.webmichelin.com/tires/18/loadandpressure.html
  4) Weight reduction is critical to all army systems.  The lower 
the weight, the more appealing the proposal.  The weight of a Michelin 
11.00R16 military tire assembly weighs approximately 222 lbs.  Technical 
information may be found at the following link:  
http://truckus.webmichelin.com/tires/17/specs.html
  The XL tire width is 10.9 inches and overall diameter is 38.7 inches   
and the XML tire diameter is 44 inches and width is 12.2 inches.  
  From this information I estimate that the XML tire assembly is 
approximately 280 lbs (taking into account the XL tire is mounted on
a steel rim and the XML tire is mounted on an aluminum rim.  I will   
contact the PM for this specific information.
  5) This is the distance a tire can travel damaged before maintenance 
is required.  Worst case scenario will be all four tires shot out on 
one side.
  Run-Flat Capability:  150 miles at 50 miles per hour
  Ballistic Capability against the following ballistic threats
	0.44lb PMN mine 75 miles at 50 miles per hour
	30 mm HE round 75 miles at 50 miles per hour
	30 mm KE round 75 miles at 50 miles per hour
	M74 Bomblet 75 miles at 50 miles per hour
  One more critical aspect of the current system is that tires & CTIS 
system allow for raising and lowering the vehicle by adjusting the air 
pressure.  This is sometimes critical in transporting the system and 
something participants may wish to address in their proposal submission.


Q: I would like to know if there is a "buy American" restriction.  
I represent an Israel-based client that has developed the technology 
that meets the requirements for the solicitation. 

A: I know of no Buy American restrictions.


Q: Does TACOM have stiffness and damping characterization data for 
the current IAV pneumatic tire that would be available upon award?
  If not, can TACOM provide a wheel and tire combination for testing 
upon award?

A: The dampening and stiffness characteristics are Proprietary to Michelin,
Michelin 12.00R20 XML, and cannot be supplied to competitors.  PM-BCT
will need to supply the requested items; wheel, run-flat insert, and
tire.
  Since I work for the Program Manager's Office for Light Armored Vehicles
I cannot speak for the BCT/IAV folks but I would like to think that they
will cooperate with these types of requests.


Q: From the information we have learned, we would like
to suggest the following:
  1. A radial "All Purpose" traction tread tire which would be capable 
of carrying 5000 lbs. at 58 psi.
  2. The dimensions of these tires are:
	Overall Width: 12.8"
	Overall Diameter: 41.0"
	SLR: 18.6"
	Carrying Capacity at 65MPH is 5000 lbs at 58 psi
	On 8 tires this totals a load capability of 40,000 lbs.
  3. The tire weight with the appropriate protector from ballistic threats 
and wheel would be approximately 360 - 400 lbs. for the complete assembly.
  4. We believe that the tires would have the "run flat" capability of
traveling 150 miles at 50MPH.
  Please confirm to us that the tire dimensions and carrying capacities note
at 58 psi would be acceptable. Also confirm that the total weight would also
be okay. Please note that an indoor wheel test could be done that would
definitely demonstrate the capability of traveling the 150 miles at 50MPH
without air. If the wheel test proves out, we would be willing to produce
sample assemblies for prototype testing.

A: 1) The max tire load for the Michelin XML 12.00R20 tires used on the 
Stryker (IAV) is 7165 lbs per tire at a PSI of 105.  Please see the link 
below to Michelin's website:
	http://www.michelin-us.com/us/eng/tire/truck/tires/pdf/xml.pdf 
  2) The Michelin XML tire used on the Stryker (IAV) has the following 
characteristics:
 - The dimensions of these tires are: 
	Overall Width: 12.2" 
	Overall Diameter: 44.5" 
	Load radius: 20.7" 
	Max tire Load at 62 MPH is 7165 lbs at 105 psi 
 - The weight of the Stryker is ~ 37,000 - 38,000 lbs. 
  3) The complete assembly should not weigh more than 300 lbs (this does 
not include CTIS hardware).  The lower the weight the better.
  4) The tires sould have the "run flat" capability of traveling 150 miles 
at 50MPH.  However, as the SBIR states, the current capability is 30 miles 
at 30 MPH at run-flat state.  A participant must beat this capability to 
be considered.  The goal is for the Stryker to be able to travel 150 miles 
at 50 MPH in run-flat condition.  The max speed of the vehicle is 62 mph, 
so any improvement over 62 mph will have minimal or no impact.  


Q: We have a new more practical and feasible CTIS design.  This CTIS would 
work with existing tire-wheel assemblies for the IAV in addition to any and 
all proposed airless tire-wheel concepts proposed for the IAV.  We would like 
to know if our proposal would be considered for Phase I funding without 
proposing an airless tire-wheel prototypes? 

A: I need more detail of the proposal objectives to make a statement 
(saves weight, lower cost, more survivable, etc).  I will say one thing, 
weight is critical.  If you can save weight, your concept may have merit.  
I left a message at the Help Desk (866)724-7457 regarding the possibility 
of combining your proposal to another proposal to make an optimal proposal.  
You may wish to contact the Help Desk yourself.  It would be simpler to 
include a tire/wheel design that would enhance the survivability.


Q: 1) The tire that we now have available has dimensions noted in my 
previous query, i.e.: 41.0" OD  12.8" OW   SLR 18.6"
  Since the carrying capacity needed is sufficient with this tire would 
it be considered or must it conform to the pre-selected 1200R20 XML?
  2) The weight we now have for our "run flat system" is about 375 lbs.. If
the performance of our tire & wheel "run flat system" is truly proven to do
50 mph for 150 miles, would the current tire we have be acceptable for this
vehicle?  Alternatively, would a new tire with the exact dimensions of the
1200R20 XML be required? If it would, it of course would be heavier.
  3) Please advise the quantities of tires and wheels of the "run flat system"
that are projected to be required over the near term and long term? We want
to make sure we have the capability  to meet the needs, if our "run flat
system" proves to be of interest.
  4) Would you like us to perform a preliminary indoor wheel test that would
prove definitely that our "run flat system" on our current tire would do 50
mph for 150 miles?  Please advise and confirm your thoughts reference this
test.

A: See answers above.