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View Full Version : B-2 Bomber crashes....................


chudson
06-10-2008, 10:00 AM
Both pilots ejected safely...........................

http://www.foxnews.com/story/0,2933,364185,00.html

puck_11
06-10-2008, 02:35 PM
Woh, thats old news there buddy, that happened back on Feb 23rd! I thought there was another crash.

shepherd
06-10-2008, 02:39 PM
1.4 billion dollar aircraft

117 million taxpayers in the U.S.

Where do I send my $12.00 ? :mad:

I guess the pilots can't manually fly that plane without the computer? I bet that's a popular feature of this aircraft. :rolleyes:

djhuff
06-10-2008, 04:22 PM
There is no manually flying a B-2. There are so many fine adjustments that allow a flying wing to remain stable, we haven't figured out how to get the human brain to think and react to that many inputs.

shepherd
06-10-2008, 05:59 PM
I thought I remembered reading that. I'm just saying... I bet there aren't a whole lot of pilots out there who like the idea of being in a plane they wouldn't be able to control when things went to ****. In fact, I know some old-timers who would say you aren't reallly flying that plane even when it's operating correctly.

Piper Cub... now that's REAL flying! :D

MYMC
06-10-2008, 07:27 PM
Woh, thats old news there buddy, that happened back on Feb 23rd! I thought there was another crash.

Puck, Carrier landing yet?

MYMC
06-10-2008, 07:30 PM
There is no manually flying a B-2. There are so many fine adjustments that allow a flying wing to remain stable, we haven't figured out how to get the human brain to think and react to that many inputs.
But the "wing" has flown without all the computers...http://en.wikipedia.org/wiki/Northrop_YB-49

Tom023
06-10-2008, 07:40 PM
Forgotten Lesson Caused B-2 Crash


Jun 6, 2008

David A. Fulghum/Aerospace Daily & Defense Report

Crews and maintainers never formally recorded information on a vulnerability involving the B-2’s air pressure sensors and the simple workaround crews came up with to mitigate it, a crucial omission that set the stage for a Feb. 23 B-2 crash in Guam.

Aircrews and maintenance teams learned about the sensors’ susceptibility to moisture during a Guam deployment in 2006. They also discovered that turning on the 500-degree pitot heat would quickly evaporate the water and the flight computer would receive normal readings.

But the information was not formally “captured” in maintenance or lessons-learned publications, said Maj. Gen. Floyd Carpenter, president of the accident investigation board and vice commander of 8th Air Force. The result was that by the 2008 deployment, the information was passed on by word of mouth so that “some people knew about it and some people did not,” he said during a Pentagon briefing June 5. Crews never encountered the problem at the bomber’s home base of Whiteman Air Force Base, Mo.

Earlier incident

Earlier in the 2008 deployment, another B-2 had reached 70 knots in its takeoff roll when abnormal indications caused the pilot to abort. The aircraft taxied back to maintenance, the moisture was evaporated with pitot heat and the mission continued without incident.

But on Feb. 23, calibration of the sensors was done without turning the sensor heaters on. The skewed information from three of the 24 air pressure sensors on the Spirit of Kansas fed distorted information into the flight control computer. When the aircraft reached 130 knots, the computer thought it was at the 140-knot takeoff speed and rotated for takeoff.

The sensors also indicated the bomber was in a nose-down attitude so it commanded a rapid pitch up that reached 30-31 degrees before the pilots could correct and stop the climb at an altitude of about 80 feet. The effects of the low takeoff speed and high angle of attack caused the B-2’s speed to deteriorate until the aircraft stalled and began a roll to the left, when its left wing tip struck the ground. At that point the pilots ejected (Aerospace DAILY, March 28).

The aircraft’s remains were boxed and will be sent to the U.S., where the cockpit, seats and hatches will be used for training.

Additional information, including the crash investigators report and video, is posted on Air Combat Command’s Web site at http://www.acc.af.mil/aibreports/.

bigmac
06-10-2008, 07:42 PM
I guess the pilots can't manually fly that plane without the computer? I bet that's a popular feature of this aircraft. :rolleyes:That's nothing new. I believe that the F16, F18, F22...in fact most modern military aircraft, are digital fly-by-wire and susceptible (in theory) to the same issues that caused this B2 crash. No manual control.

puck_11
06-10-2008, 08:05 PM
Puck, Carrier landing yet?

Oh yeah! Carrier qualed baby! I got my 10 traps under the belt out in San Diego on the USS Stennis 3 weeks ago! Theres nothing like a cat shot sending you from 0-130kts in 2 seconds :D I'm 10 flights from wings, I'll give a little write up on here when I'm all done!

puck_11
06-10-2008, 08:09 PM
1.4 billion dollar aircraft

117 million taxpayers in the U.S.

Where do I send my $12.00 ? :mad:

I guess the pilots can't manually fly that plane without the computer? I bet that's a popular feature of this aircraft. :rolleyes:

My aerodynamics professor in college told us about the F-117 and all of its redundant computers. If they all fail, the aircraft is so inherently unstable that it will go out of control in under .4 seconds (or something ridiculous like that)

puck_11
06-10-2008, 09:26 PM
That's nothing new. I believe that the F16, F18, F22...in fact most modern military aircraft, are digital fly-by-wire and susceptible (in theory) to the same issues that caused this B2 crash. No manual control.

That's not entirely true. They are all fly by wire, meaning that you pull the stick back and it sends an electronic input through a computer to an actuator which moves the control surface. That is instead of using mechanical linkages like a Cessna or hydraulics like most airliners or the mighty T-45. The reason that the B2 and the F117 can't fly manually is that they are a flying wing and inherently unstable. The computers need to do their magic to keep it flying. You can read up on aircraft stability here http://www.allstar.fiu.edu/aero/axes33.htm

A fighter like the F-18 is more stable and can actually fly manually. Having never flown it all my knowledge is second hand info, but the rudder is manually controlled and an F-18 that had lost all electrical power was able to trap aboard a carrier using only rudder inputs and throttle movement :eek3:

The way the flight control system in the F-18 works is phenomenal. It will give you everything the airplane is capable of without departing it, in a max performance turn it will configure every flight control surface, including the flaps to give you whatever you want.

chudson
06-11-2008, 01:20 PM
Woh, thats old news there buddy, that happened back on Feb 23rd! I thought there was another crash.

Ya know I saw that on Fox yesterday morning and thought it was new and I must of been asleep the day it happened but the video was just released yesterday they said. Still a pretty sad thing to see happen!!!

flipper
06-11-2008, 01:27 PM
Congrats puck, I've herd that a carrier landing isn't a landing at all. More like a controlled crash.:D

puck_11
06-11-2008, 04:17 PM
Thanks it was a lot of fun. From the carrier series on PBS:
"Landing on a carrier is like having sex during a car accident."

bigmac
06-11-2008, 05:22 PM
That's not entirely true.

A fighter like the F-18 is more stable and can actually fly manually. Having never flown it all my knowledge is second hand info, but the rudder is manually controlled and an F-18 that had lost all electrical power was able to trap aboard a carrier using only rudder inputs and throttle movement :eek3:


I apologize for getting that wrong. My understanding has been that only the F/A-18 A/B and C/D have mechanical stabilator backup, whereas the Super Hornet (in use since 1995) doesn't - mechanical backups all being replaced by the reconfigurable FCS as of Block II - IOW entirely fly-by-wire.

puck_11
06-12-2008, 01:16 PM
I apologize for getting that wrong. My understanding has been that only the F/A-18 A/B and C/D have mechanical stabilator backup, whereas the Super Hornet (in use since 1995) doesn't - mechanical backups all being replaced by the reconfigurable FCS as of Block II - IOW entirely fly-by-wire.

Well, that may be true. I'll get back to you on this one, I'll ask some of my IPs. Apparently you know a little bit about the Hornets :) Like I said before all of my knowledge is second hand. Hopefully I'll be in ground school within the next couple of months and I can let you know for sure!

MYMC
06-12-2008, 02:35 PM
Oh yeah! Carrier qualed baby! I got my 10 traps under the belt out in San Diego on the USS Stennis 3 weeks ago! Theres nothing like a cat shot sending you from 0-130kts in 2 seconds :D I'm 10 flights from wings, I'll give a little write up on here when I'm all done!

Congrats...looking forward to seeing the write up!

Willski
06-12-2008, 02:36 PM
Thanks it was a lot of fun. From the carrier series on PBS:
"Landing on a carrier is like having sex during a car accident."

Oh. You are not supposed to do that?