NTSB: Plane hit antenna off the end of runway

By LIZ FEDOR, Star Tribune
August 2, 2008
The right wing of the Raytheon Hawker 800 jet involved in Thursday's fatal crash at the Owatonna airport hit an antenna about a thousand feet past the end of the runway after the pilot tried to land the plane, a federal official said Saturday.
"The antenna stands about 8 feet high and straddles the width of the runway," said Steven Chealander, a board member for the National Transportation Safety Board (NTSB), the federal agency investigating the crash.
Chealander said a dozen NTSB investigators are remaining in Minnesota, as they continue to gather evidence to help them determine what caused the crash.
He said in an interview that they have recovered a third device -- which monitors the plane's proximity to the ground -- that could give them some additional clues.
But on Saturday he revealed more details about how the crash unfolded.
"We have witness accounts that it did touch down and [the pilot] was trying to land and during the landing roll out, for some reason they made a decision to try to take off and get airborne again," he said.
But the NTSB official said the plane instead ran off the end of the runway, traveled through a grass field and struck an antenna, which is part of the instrument landing system at the Owatonna airport.
"The airplane was still on the ground when it hit that antenna, and the accident sequence began at that point and [the plane] ended up in that cornfield," he said.
The two pilots and six passengers on board the charter flight all died from their crash injuries. The passengers were flying from Atlantic City, N.J., for a business meeting at an Owatonna glass manufacturing company.
There were strong winds and storm systems in southern Minnesota prior to the accident, but Chealander cautioned Saturday that it is too early to reach any conclusions about the accident.
"We are looking at all aspects of the flight, not just focusing on any one thing," he said.

On Monday, NTSB representatives will gather in a lab in Washington D.C. to dissect what was captured on the cockpit voice recorder. Shortly after the crash, they also recovered the flight management computer.
Chealander said Saturday that investigators found a box late Friday afternoon that contains the "enhanced ground proximity warning system." Essentially, it warns pilots about their distance from terrain.
Honeywell manufactured the product. "Honeywell will take the box to one of their laboratories and determine whether or not it has any memory trace or trail in it that we can use," he said.
Staff members from the Federal Bureau of Investigation, who are mapping the crash debris on site, and the Federal Aviation Administration are working with the NTSB. Chealander said three witnesses were interviewed in Minnesota on Friday and another witness was scheduled for an interview on Saturday.
In addition, the NTSB is talking to people on the ground in Atlantic City and in Allentown, Pa., where the pilot crew was based. Information also is being gathered from air traffic controllers and the National Weather Service.
Chealander said he's confident that the NTSB will pinpoint the cause or causes of the crash, but a final report won't be issued for several months. "Within the next week or so, you'll see a preliminary report of what we've found so far," he said. But that report will cite accident facts, not a conclusion about a cause.

Photo of crash site:
http://www.startribune.com/photos/?c...0crash0801.jpg

If anyone cares, the airplane was N818MV.

I had the opportunity to spend 3 hours at the site with the NTSB as well as the accident invesigator aasigned by the IC.

I will leave the speculation about micro-burst and meso-scale events to the weather experts and relate what I observed. I have no time in this model and will pose specific questions that I hope you can help with.

1) according to an eye witness, the plane touched down in the 1st 3rd of the 5500 ft runway. He cancelled IFR, but we do not know if he was flying the needles, the PAPI or trying to hit the 1st brick.

2) the runway was soaked to the point where the witness observed "major splash" from the tires.

3) at some unknown point, the PIC initiated a go -around attempt

4) the plane crossed the end threshold and began to traverse a 1000 foot wide grass over run that would have been suitable for a Maul. Main and nose wheel tracks were observed to the localizer array. The nose wheel seemed to lift and settle at least once.

5) the right wing impacted the localizer array at about 8ft agl.

6) The ground then drops away and the right wing enters the corn 150 to 200 yards on the other side of a culvert and tumbles

My questions are these:

The fans were 19 years old...how long to spool up from idle to T/O power ?

Flaps are at 85+ degrees for landing. If The PIC calls for flaps at 15...how long does it take before the wing is getting lift and not drag ?

Based on 1/2 full tanks and 8 people and assuming a hydroplane event with full ABS engagement, how far does this bird roll with little or no braking and engines at idle? In other words would a rollout into a 1000 foot soft mud field been survivable or would the inertia have taken them into the culvert ?

I had the opportunity to spend 3 hours at the site with the NTSB as well as the accident invesigator aasigned by the IC.

I will leave the speculation about micro-burst and meso-scale events to the weather experts and relate what I observed. I have no time in this model and will pose specific questions that I hope you can help with.

1) according to an eye witness, the plane touched down in the 1st 3rd of the 5500 ft runway. He cancelled IFR, but we do not know if he was flying the needles, the PAPI or trying to hit the 1st brick.

2) the runway was soaked to the point where the witness observed "major splash" from the tires.

3) at some unknown point, the PIC initiated a go -around attempt

4) the plane crossed the end threshold and began to traverse a 1000 foot wide grass over run that would have been suitable for a Maul. Main and nose wheel tracks were observed to the localizer array. The nose wheel seemed to lift and settle at least once.

5) the right wing impacted the localizer array at about 8ft agl.

6) The ground then drops away and the right wing enters the corn 150 to 200 yards on the other side of a culvert and tumbles

My questions are these:

The fans were 19 years old...how long to spool up from idle to T/O power ?

Flaps are at 85+ degrees for landing. If The PIC calls for flaps at 15...how long does it take before the wing is getting lift and not drag ?

Based on 1/2 full tanks and 8 people and assuming a hydroplane event with full ABS engagement, how far does this bird roll with little or no braking and engines at idle? In other words would a rollout into a 1000 foot soft mud field been survivable or would the inertia have taken them into the culvert ?

Let me try to answer those questions for you....

The engines will spool relatively quickly, maybe 4-5 seconds from idle to full power, maybe less. These engines had the N1
DEEC's and resonded quickly to full power requests.

Lift dump on landing causes the flas to go to 75 degrees(from what I remember), and a go around on a short runway after lift dump engagement can be tricky. Lift dump traps the flap handle at 45 until the lift dump is disengaged so the fo cannot move the flap handle on a go around attempt until the captain moves the airbrake handle out of lift dump. The flaps travel very quickly from full dump to 15 if everything is done correctly however, and this is purely my opinion as someone with a couple thousand hours in the airplane, the hawker cannot get back up to rotation speed after lift dump is selected on a 5500 ft runway.

Unfortunatly, and this is the part that haunts me everyday, with lift dump selected the aircraft decelerates nicely, similar to thrust reverse at idle, and had the crew simply let the aircraft roll without any braking and shut down the engines, it probably would have settled into the mud at the end of the runway. We dont know right now if there were any other factors in play that caused the rejected landing attempt, so it may not have been this obvious.

Radar track and wx overlay.



The ATC recording with the + or - 20 kts is from RST that is 20+ miles away.

I don't know anything that has 85 degrees flaps, could it be 85% flaps?

Fli

The hawker landing flap setting if flap 45 degrees, upon landing the capt. goes into "lift dump" this causes the airbrakes to fan out to 85 degrees and the flaps to 75 degrees. Their is a high speed motor which causes it to happen very fast. At this point their is a lot of drag on the airplane. 5500 foot runways are a common occurance in hawkers, however on the 800 their is no published wet runway data. The antiskid system works very good on the airplane. Once liftdump is selected is would be difficult to do a rejected landing, especially if it wasn't briefed prior. The capt and fo would both have to be aware what was going on in order to sucussfully complete the task. even if they did brief it I still don't think it is do able on a 5500ft. field. They would have gotten a config warning horn since the airbrakes were extended and PLA was above mid range. But i'm sure they wouldn't have the reaction time to undo their actions with not much runway left.

DSF

So at what point is this lift dump activated? What if they are on short final and need to do a go around? What if they are just touching down on the runway and encounter a major crosswind? I'm no pilot, yet, but this system sounds like an accident waiting to happen.

The Lift Dump is deployed when the aircraft touches down. The flaps go to about 75 degrees and the top and bottom spoilers go from about 50 degrees to about 80 degrees. This aids in aerodynamic braking.

Lift dump has to be stowed prior to flap retraction.

A dry landing at a a high weight will require about 4,000 of runway. The aircraft can actually be stopped in 60% of this value. If the flight was conducted under FAR135 then an additional 15% of runway would be needed on a wet surface. The Hawker does have non-FAA approved data for wet and contaminated runway conditions in the Flight Manual Suppliments.

So how would one de-activate "Lift Dump". It seems to me that when Max Power or Go Around is initiated the "Lift Dump" retracts the leading and or trailing edges devices and doesnt lockout flap retraction. Not a hawker wizard but that could be a lawsuit in the making.. my 2cents