Military History | How To Make War | Wars Around the World Rules of Use How to Behave on an Internet Forum
Armor Discussion Board
   Return to Topic Page
Subject: EFV Replace: whats the best deal?
jessmo_24    3/17/2011 6:19:39 PM
EFV Replace: ‘What’s Best Deal’ EFV Replace: ‘What’s Best Deal’ By Colin Clark Wednesday, March 16th, 2011 4:42 pm Posted in Land, Naval, Policy The Expeditionary Fighting Vehicle became the focal point again for congressional unhappiness with the secrecy with which the Gates’ Pentagon does business during a hearing of the House Armed Services seapower and projections forces subcommittee. “It’s a systemic problem,” Rep. Todd Akin, chairman of the committee, told me after the hearing. “it’s an increasingly systemic problem” In his prepared statement, Akin said he feared “that when it is all said and done, the Marine Corps will probably only get an upgraded version of the current Amphibious Assault Vehicle (AAV).” However, Stackley said that would not happen. The service had concluded that upgrading the AAV would just be too expensive. Marine Lt. Gen. George Flynn told Akin the next key step would come when the Marines host an industry day at the end of the month. Akin was not alone in expressing his unhappiness with how the Pentagon made its decision about canceling the EFV. The chairman was joined by Rep. Roscoe Bartlett, chairman of the of the HASC air and land forces subcommittee, raised the issue during the hearing, telling the Navy and Marine leaders testifying before him that he wanted to be involved in the process for determining the replacement for the EFV. A scientist by training, Bartlett noted that Akin is an engineer and they would both be capable of knowledgeably participating in the process. Bartlett told reporters after the hearing that he would like to take part in war games involved in crafting the new amphibious requirements and to be regularly briefed on important program decisions before they are made. He said he’d been invited to two or three war games in his 17 years in the House. It was unclear whether he had participated or attended those to which he had been invited. As part of that effort to open up the Gates Pentagon, Akin pressed Sean Stackley, head of Navy acquisition, to brief his subcommittee on the EFV’s possible replacements. They tentatively set a date of April 7. Akin’s ultimate criteria for an EFV replacement? “What’s the best deal” that also gets Marines in relatively safety and comfort from ships at sea 12 miles out into the shore with enough speed. Flynn told the panel that the Marines have modified the requirement from 10–22 miles to 12 miles. Read more: http://www.dodbuzz.com/2011/03/16/efv-replace-whats-best-deal/#ixzz1GtjTGnyc Why cant the stryker be modified for the marines? It would give them a common chassis.
 
Quote    Reply

Show Only Poster Name and Title     Newest to Oldest
WarNerd       3/18/2011 5:54:58 AM

Why cant the stryker be modified for the marines? It would give them a common chassis.

The Stryker is not amphibious. 
 
The old LAV-25 (LAV II) was amphibious, but it was also 20% lighter.  It had a top speed of 12kph and could not handle surf/rough water.  The LAV-25A2 upgrade is no longer amphibious.  The problem apparently lies in the need to increase armor protection to handle 14.5mm AP fire.
 
Quote    Reply

doggtag    one possible MPC candidate   3/18/2011 8:49:04 AM
I read quite a bit on this one ( IVECO SuperAV 8x8 ),
doesn't seem like a bad contender at all.
Question remains as to what levels of surf it can handle (technically, it is a ground vehicle first, a watercarft second).
 
Still, it swims (or at least floats and makes the effort), which none of the Strykers do.
If anything, it should be useful for river crossings and the occasional pond, shallow lake, estuary, or marsh that gets in your way (like most wheeled vehicles though, advise against taking on the mud beds and sand bars.
 
The negative slant of it, a completely new logistics trail,
but then again, the EFV would've also.
And it's been suggested that it would be built in the US, were it selected.
 
If high water speed is deemed a must, maybe design concepts like these could be militarized (just as bigger vehicles, not these car- and jeep-sized designs).
Biggest challenge being, metal alloy armors, even thick Kevlar, are going to add so much more weight than what these fiberglass/composite (aliminum skinned?)  hulls are made of.
 
Other issue is, a military-grade suspension would be composed of some structurally heavy components: it remains to be seen if thicker parts can be made to operate (retract/extend) in a similar drag-reducing fashion.
 
The basic V-hull design of these personal watercraft should lend considerably to deflecting underside blasts like mines and IEDs.
 
Quote    Reply

LB       3/18/2011 5:42:43 PM
The main issue  is the USMC plans on a light, medium, and heavy infantry carrier with the heavy carrier being the amphibious assault vehicle.  If they stick with this then the you end up with something like the EFV but without the water plane ability and the 2,500 hp engine.  The new requirement is for a I believe to transit 10 miles in an hour so you the main thing is getting around 10 knots water speed instead of the much higher required speed of the EFV.
 
There's a lot of good reasons for combining the assault and heavy infantry carrier role but personally the Corp might take a 2nd look at the assault vehicle being the medium carrier and then just buying an IFV.  In any case the medium infantry carrier is a Stryker class vehicle which can not meet the assault requirement.
 
Quote    Reply

VelocityVector       3/18/2011 8:06:34 PM

Design an unarmored, diesel-engined and conformal amphibious stability shell for each of the existing Marine armor types except for M1A1 and specialty kit.  Allow tracks to protrude if sandbar or reef encountered.  Jettison the shell once on beach.  Transport heavies by LCAC.  Then, Marine armor doesn't need to fight while carrying useless weight.  Reclaim and reuse the shells if victorious; if defeated then shells are the least of your worries.  Accept the performance limitations and live or die by superior aviation and fire support.  Either that else fold Marines into some other service branch.  0.02

v^2

 
Quote    Reply

WarNerd       3/20/2011 2:42:06 AM

Design an unarmored, diesel-engined and conformal amphibious stability shell for each of the existing Marine armor types except for M1A1 and specialty kit.  Allow tracks to protrude if sandbar or reef encountered.  Jettison the shell once on beach.  Transport heavies by LCAC.  Then, Marine armor doesn't need to fight while carrying useless weight.  Reclaim and reuse the shells if victorious; if defeated then shells are the least of your worries.  Accept the performance limitations and live or die by superior aviation and fire support.  Either that else fold Marines into some other service branch.  0.02

You have just increased the volume of the vehicles that you need to transport by 150%  and the weight by 50%. 
Top speed will be less than 6 knots.
 
Quote    Reply

LB       3/20/2011 4:43:36 AM
This isn't really difficult.  The original requirements were met but required a 2,700hp water planing IFV that was very complex and very expensive to go 30 mph on water.  The AAV-7 goes about 9 mph and makes Marines sick because it rocks around, leaks, and is poorly ventilated.  The engine is about 500hp.
 
What is required is around 12 mph which can be done without the water planing in a new well ventilated, dry, and stabilized vehicle.  The original requirement that produced the EFV was based on a problematic doctrine which has since been changed. 
 
Quote    Reply

WarNerd       3/20/2011 11:28:28 PM

This isn't really difficult.  The original requirements were met but required a 2,700hp water planing IFV that was very complex and very expensive to go 30 mph on water.  The AAV-7 goes about 9 mph and makes Marines sick because it rocks around, leaks, and is poorly ventilated.  The engine is about 500hp.

What is required is around 12 mph which can be done without the water planing in a new well ventilated, dry, and stabilized vehicle.  The original requirement that produced the EFV was based on a problematic doctrine which has since been changed.

A non-planing hull for 12 mph would have to be at least 60 ft long, probably closer to 85 ft, to do 12 mph with a hull less than 30 ft will require a lot of power.
 
Looking at the AAVP-7, the speed appears to be limited by the ability to deliver power to the water, even allowing for the lousy shape power requirements are likely to be less than 30% of 400 - 500 BHP available.  It will take at least 6 x the HP delivered to the water to go 12 mph as 8 mph in the same hull as the AAVP-7.
 
As for the handling, not much you can do without drastically increasing the size.  And the lousy ventilation is a function of the low freeboard, the last thing you want is to ship more water than it already does.
 
Quote    Reply



 Latest
 News
 
 Most
 Read
 
 Most
 Commented
 Hot
 Topics