For LO and so on...
US Navy solves X-47B tailhook problem in-house - IHS Jane's 360
Richard Scott, London - IHS Jane's Navy International 09 September 2012
The US Navy (USN) has admitted another problem with a new aircraft tailhook design, this time affecting the Northrop Grumman X-47B Unmanned Combat Air System Aircraft Carrier Demonstration (UCAS-D) programme.
According to a release issued by Naval Air Systems Command (NAVAIR) on 5 September, the service was forced to urgently task its Fleet Readiness Center South West (FRCSW) at Naval Air Station (NAS) North Island, California, to redesign and manufacture new hook points for the X-47B after arrestment roll-in tests revealed problems with the original design.
"In late spring, a team from Patuxent River, Maryland, called on FRCSW at NAS North Island to redesign the hook point for ... the X-47B UCAS-D", NAVAIR said. "When unsuccessful roll-in arrestment tests of the X-47B revealed the need for a modified hook point, the team needed to come up with a plan to make the modifications in order to perform arrested landings and catapult launches this fall [autumn]."
According to NAVAIR, the FRCSW signed a formal work order on 10 July, anticipating the manufacturing and shipping process would take up to one month. However, the engineering and manufacture of the hook points took slightly longer; for example, machining the first steel part took longer than expected, as a result of which the FRCSW invested in a more efficient machine to decrease cycle times.
Navy Preps For X-47B Cats, Traps On Carrier
Navy Preps For X-47B Cats, Traps On Carrier
December 10, 2012
By Amy Butler, Graham Warwick
Northrop redesigned the X-47B tailhook because engineers had placed it too close to the landing gear. The distance didn't allow the landing cable to bounce and rest back on the ground so the tailhook could scoop under the cable and connect to it. The problem is similar to that experienced by Lockheed Martin with the F-35C tailhook. The redesign, executed in 45 days, has proven successful in three arrestment roll-in demonstrations, says Capt. Jamie Engdahl, Navy UCAS program manager.
Arrested landing trials are slated to start early next year.
But this didn't fix the problem...
The day of the unmanned aircraft. - The DEW Line
By Dave Majumdar on May 15, 2013 12:02 AM
Meanwhile, the US Navy launched a Northrop Grumman X-47B from the USS George H W Bush earlier today--our very own Zach Rosenberg was there. The Navy got Flightglobal a slot on the helicopter even though they initially told us there was no room. The launch looks like it was quite successful--take a look below.
However, the X-47B did not carry out an arrested landing upon returning to Pax River. That could be because the unmanned jet was having difficulty making even that first trap it did the week before where the Navy showed off a video of the aircraft snagging a wire. Sources told the DEW Line, at the time of the earlier trap, the aircraft now had a 10 percent field boarding rate... So hopefully, this isn't an indication of a major problem. The X-47B guys have had to redesign their tail hook a number of times now due to the same inaccurate Navy-supplied wire dynamics model that was partly responsible for the F-35C's woes.
So, in the first week of May 2013,
some 5 months after the USN claimed to have "solved" the X-47B's tailhook problems,
it still had only a 10% success rate!
Sounds like Killface's friend is correct.