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Schlagen aus der Nachhand
What you call "mobile defense" (otherwise known as "elastic
called by the Germans "Schlagen aus der Nachhand" (can't translate
Nachhand is a highly unusual word now).
Ed: I've read that "elastic defense" is a better
translation from German, but the US Army uses "mobile defense,"
probably because some may assume elastic defense means "defense in
depth." Another crafty WW II German tactic was to abandon the frontline
when a Soviet offensive seemed imminent, leaving behind a few reconnaissance
units to keep the front looking active. Then the Soviet's massive
artillery barrage would cause little damage and Soviet assault troops would run
into the main German defense line two kilometers later, untouched by the
Did the Iraqi ‘resistance’ use this tactic of counterattack you refer to as Intercepting Fist in March of 2003?
An intercepting fist was used in small battles, accidentally. It
seems their defense plan was so screwed up they just attacked whatever they
Ed: An intercepting fist was used in small battles, accidentally. It seems their defense plan was so screwed up they just attacked whatever they encountered.
Great issue as always!
The intercepting fist tactic is what is being used against us in Iraq. Ever heard the old infantry adage, "if the enemy is falling back, its an ambush coming up."
Chess is good but the game of "Go" from Japan may be much better with its concept of territory acquisition.
Agree on seabasing. I just think its a new way to spend money for something that U.S. industry can build.
Small commercial trucks - Great idea!
Films - no "Blackhawk Down?" Please reconsider. I could just be too influenced by the book.
I'll add "Blackhawk Down." I was disappointed in the movie the first time I saw it because it was much more shallow than the great book. I saw it again a couple months back; it's unique and has great combat scenes so I'll add it to the G2mil list.Modern Jeeps
Wow. Excellent points. The Toyota is prevalent in the third world
shitholes we fight in, they can be had in various configurations, 4wd, and
diesel power. They're fast, agile, and pretty damn tough, considering.
Basically, I support stripping them down to CUCV type specs. Goal is a light,
mobile vehicle for scouting, loggo support, light-and-fast moves, spec ops,
general a-to-b transit, and sale on the surplus market as a BOV.
Ed: I was surprised to come across this article http://www.nationaldefensemagazine.org/issues/2005/Feb/SB-Army_Not.htm in the excellent National Defense magazine which describes how the Army's Detroit research branch has been pitching the idea of a small, low-cost, reliable commercial truck.
Go is Better than Chess
I was amused by your article on chess. I know it has a serious
intent, but the simplicity caught my attention. At no time in my army
training was something so simple mentioned. But there is better; I think the Japanese game of 'Go' is superior to
chess. It has only two pieces: white and black stones; which are used to
'capture territory' by some very simple rules. However, like a lot of
oriental things, the simplicity belies a great complexity of thinking
required for mastery. I still can't beat my computer in a 16 square
game, let alone the full board, after a few years of on and off
Ed: The G2mil Winter issue included an internal USMC briefing as to why the V-22 Osprey is unsafe. I have been provided with an updated and expanded version which I used to update that article: Why the V-22 Osprey is Unsafe Note this new section:
The results of these numerical calculations confirmed my rough calculations and raised my concern level, which I communicated to DOT&E. Pursuant to this issue, in mid-2001, XXX, through DOT&E, requested the Program to conduct flight testing with V-22 to include three evasive maneuvers that I believe pilots might resort to in combat to avoid enemy fire.
In a subsequent technical interchange meeting in late 2002, the Bell/Boeing-NAVAIR team agreed, in principle, that the maneuvers should be done and embarked on an flight test program to include these maneuvers. To date these maneuvers have not been accomplished because the V-22 rotor control system repeatedly exceeded rotor disk flapping limits while approaching the requested conditions. The inability to maneuver V-22 in this fashion without exceeding rotor flapping limits is a serious safety concern in itself and argues against the ability of V-22 to safely perform evasive maneuvering in a combat environment.
This matches comments later in that article:
Because of this lack of blade flexibility, sharp maneuvers have caused new lightweight composite parts in V-22s to break during testing, so further tests were recently cancelled. The Fort Worth Star-Telegram published an investigative report on September 26, 2004 by Bob Cox on recent V-22 testing which noted:
Some testing was done. But a series involving specific, sharp defensive maneuvers was skipped after Bell engineers warned that it would severely damage the rotors, according to a source within the testing program who asked not to be identified for fear of losing his job.
Several people told the Star-Telegram that the canceled tests are important.
Program officials feared the maneuvers would damage the aircraft.
Tom Christie, the chief weapons tester for the Pentagon, acknowledged to the Star-Telegram that the "most severe maneuvers" were not conducted during recent testing. When asked whether the skipped tests signal shortcomings that could affect the V-22's performance in combat, he did not answer directly.
"The tactical implications of this limitation have been carefully considered and will continue to be reviewed," he said.
In short; the V-22 cannot perform combat maneuvers around an LZ, or turn sharply to avoid small obstacles in an LZ, lest it roll over and kill everyone. When flying into unknown LZs at night or in poor weather, it is not uncommon for a helicopter crew to notice a fence, ditch, large hole, cow, telephone wire, or other things right where they want to land, so the pilots must make a sharp maneuver to land nearby, which may surprise other helicopters in a formation causing them to maneuver sharply.
However, the V-22 is not a helicopter, it is more like a carrier aircraft. It may look nimble during demonstrations when it has no payload and little fuel. But when fully loaded, the V-22 must make an "approach" on a nice steady glide path. If pilots attempt evasive maneuvers to avoid ground fire or obstacles, they may cause a rotor thrust imbalance and roll over, or may overstress the rotor system, causing something to break, resulting in an instant snap roll. This tendency to roll over is deadly, and only occurs in tiltrotors like the V-22 due to the side-by-side placement of the rotors.
So will the V-22 pass the current four months of operational evaluation? Maybe, because this recent GAO report GAO Defense Acquisitions Assessments states that it may go through this final test phase with safety restrictions in place which limit the type of maneuvers pilots are allowed to perform. And keep in mind the final V-22 design will not be complete until 2009 (or later) when the "Block C" design is ready, which calls for dozens of changes and weight additions; like the gun and external hoist.
So when they state they are almost finished with testing, keep in mind they are really testing incomplete prototypes which may not be required to perform combat maneuvers. And they still haven't solved several subsystems issues. For example, the engine oil cooling fan (blower) has been a critical problem since 2001, and it continues to fail so is replaced every 100 hours. Apparently, the rotor downwash is so great that it becomes clogged and they have no solution.
Three years ago, after over a decade of development, the V-22 was declared ready to resume flight tests after a 17-month stand down to redesign this aircraft after its fourth crash. Marine Colonel Dan Schultz, the V-22 program manager, proclaimed: "All of the things that were wrong with this airplane have been fixed." Yet we still see:
STARTS OPEVAL AFTER DEALING WITH MORE GEARBOX PROBLEMS
Osprey program reached a watershed moment on the morning of March 28, when the
Navy officially began the operational evaluation for the Marine Corps version of
the aircraft, but not before the program wrestled a bit more with proprotor
gearbox problems that resurfaced last month, shortly after a senior Navy
acquisition official declared them resolved.
operational evaluation (OPEVAL), which is expected to run through the end of
June, will determine if the Marine Corps MV-22 is operationally suitable and
effective for military use. Two fatal crashes during operational testing in 2000
led the Pentagon to restructure the program. Since then, a lot of improvements
have been made to the aircraft and the overall program, officials maintain. If
the Osprey performs well in the new test phase, it will increase the likelihood
the Pentagon will buy the aircraft in large numbers.
But getting the new operational evaluation under way took a bit longer because of a recurrence of proprotor gearbox problems March 11, which prompted further investigation of an issue the Navy had described as resolved. The gearbox is supposed to translate engine power into rotor torque. But the mechanism can fail if small bits of metallic particulate matter get into the Osprey’s engine lubrication system. For that reason, the proprotor gearbox is hooked up to a warning light that illuminates if chips of metallic particulate are detected in the system.
In January, the Navy announced VMX-22, the V-22 Osprey test squadron in New River, NC, had halted Osprey flights because several aircraft experienced gearbox problems. The program office said Jan. 18 that sensors had detected that problem six times, including three incidents “in the last month.” When encountered in flight, this kind of emergency requires the pilot to land as soon as possible. At the time, the program office blamed manufacturing errors for the problems, noting those causes had been identified and were being addressed.
Initial engineering investigations revealed two root causes, both relating to components in the proprotor gearbox, the program office said in a statement to the media. Investigators discovered “improper torquing of the planetary support bearing nut” occurred during the assembly of the proprotor gearbox. This “has been remedied by a modification of shop floor procedures affecting a stricter adherence to published torque specifications,” the statement said.
root cause was “improper chroming of bearings within the input quill during
the bearing manufacturing process,” the program office said. The input quill
is the first point of attachment between the proprotor gearbox and the
engine’s drive shaft. Ultimately, the program decided to address this issue by
having industry qualify, build and deliver non-chromed bearings.
“The third root cause was originally unknown and, due to the fact it had occurred only once, resolution was prioritized behind solving the chroming process,” Carroll told ITN last week. By late February, the program and a senior Navy acquisition official characterized the gearbox problems as resolved. Thomas Laux -- the Navy’s program executive officer for air anti-submarine warfare, assault, and special mission programs -- issued a certification Feb. 24 declaring the V-22 Osprey program ready to begin an operational evaluation. This signaled Laux’s “satisfaction with the resolution” of the gearbox problems, a statement from the program office noted at the time.
But there was still the matter of the Dec. 20 incident with the unknown root cause. A reminder came March 11 when there was a seventh incident involving a gearbox problem that experts later decided was similar to the Dec. 20 event. Carroll acknowledged the March 11 incident for the first time in comments to ITN last week, noting pilots flying Osprey No. 56 had a chip caution light on the left-hand proprotor gearbox. The “initial teardown and metallurgical analysis” determined that that gearbox had also experienced a failure of the high speed planetary support bearing, he said. Further, the failure mode was identical to the “other unknown root cause,” he said.
Rear Adm. David Architzel, commander of the Navy’s operational testing force, insisted on a complete root-cause analysis and sought assurance that the problems would present a low risk in terms of safety of flight, said a Pentagon source. Carroll said the engineering team’s focus “shifted to solving the previously unknown root cause.” V-22 officials have since modified flight procedures during deceleration with the expectation that this will prevent the problem, said the Pentagon source. A long-term solution might involve changes for components in the gearbox, said the source.
Carroll said deeper investigation of in-flight data for these two occurrences
revealed that “the most likely root cause was also an excessive axial load on
the support bearing.” This was due to “a zero mast torque flight
condition” (when the gearing has little to no friction and therefore is not
providing torque to the proprotor) that engineers believe was caused by a
routine procedure for V-22 pilots. This
procedure was an unloading on the assembly that occurred when the throttle was
abruptly pulled to the aft stop and proprotor speed was increased from 84
percent to 100 percent, Carroll said.
For the time being, the V-22 test squadron and the program office have jointly developed a standardization manual change and flight clearance update to limit the zero torque condition. The safety assessment remains low risk, said Carroll. Architzel and other defense officials held a V-22 meeting March 25 to discuss the gearbox problems and solutions, paving the way for last week’s announcement on the start of the operational evaluation. The Air Force version of the aircraft, called the CV-22, is scheduled to undergo a separate operational testing phase late next year.
Christopher J. Castelli
Ed: The Operational Evaluation (OPEVAL) is the final phase of testing. It is the final exam where an outside group from the Pentagon verifies that the aircraft is safe, effective, and can perform the missions the testers claim it has ALREADY proven. However, they are pretending that this is still the development phase where problems are solved and new tests are attempted. For example, during the decade of testing they still have not demonstrated the oft advertise V-22 capability to fly to Europe with one aerial refuel. In addition, pilots are prohibited from attempting certain maneuvers, and they still have a dozen components "in redevelopment," like the blower, external hoist, gun, gearbox, extendable fuel probe, and comm system.