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-   -   Gulfstream IV in Bedford MA (https://www.pprune.org/biz-jets-ag-flying-ga-etc/540858-gulfstream-iv-bedford-ma.html)

FrankR 4th Jun 2014 04:21

... it has NOT

We should all wait for details to be reported.

Many of the "what if" scenarios presented here are completely with out merit.

glendalegoon 4th Jun 2014 05:08

FrankR

theories were proposed early on as information was slow in coming. modifications as additional information released.

things can fail Frank. just about anything can.

we are just talking here like we might in the hangar

Feathered 4th Jun 2014 05:16


Originally Posted by glendalaegoon
a thought struck me that perhaps the pilots took off from an intersection by mistake and didn't have sufficient runway for takeoff.

just a thought mind you.

doesn't it remind you a bit of the lexington, kentucky crash of the RJ, taking off on the wrong runway

I know this airport well and seriously doubt that there was an intersection take off attempted for a number of reasons.

The preferred runway is 29, assuming no wind factor. The winds that night were light to nill. Although Hanscom can get crazy busy during the weekday, after dark on a Saturday night, the airfield was probably near deserted by comparison, with just a few operations per hour. A taxi to Runway 11 is very short, since the runway starts very close to either FBO. That saves a mile and half of taxi and is likely the reason for the Rwy 11 departure. It would be interesting to hear the ATIS at the time of the accident.

There are no realistic intersection spots for a 11 departure, even for a smaller plane--the available runway at either G or F is not great for a jet. It also wouldn't make sense (even starting from runway 5-23), since you'd be taxiing parallel to a long runway and THEN taking off on the rest of it. The jet was almost certainly parked at an FBO (Jet or Signature), not on the east ramp which is adjacent to the USAF base and has limited easy access for civilians.

If the G IV had departed on Rwy 29 and had the same scenario on the runway, the outcome might have been different, as there is no downgrade and river after the runway overrun ends in that direction. But there are also trees after a long cleared area so who knows.

Astra driver 4th Jun 2014 06:53

Can no longer find the link to the Metar at the time of the accident, but basically it was winds calm and good visibility. A departure using the full length available from Runway 11 most likely offered the shortest taxi from either FBO.

tempilot 4th Jun 2014 08:56

Gulfstream IV in Bedford MA
 
Can anyone answer this: How long did it take for the crash/fire/rescue services to reach the scene of the accident?
Tempilot

Feathered 4th Jun 2014 15:14

From what I understand, fire crews arrived less than 3 minutes from the accident. They were notified immediately by the tower. The USAF provides fire and rescue on the field. Also responding were fire crews from the neighboring towns of Lexington, Bedford, and Burlington who were there shortly thereafter. An environmental team from the Bedford FD had booms in the river downstream for the crash within minutes while the firefighting crews fought the fire.

fantycloud 4th Jun 2014 15:28

Where is the coverage?
 
compare news coverage to this accident vs the aspen crash.... Is it a coincidence that it was a newspaper boss that perished? I want to know about the accident and the news sites are sush.... guess we wait for NTSB report.

robbreid 4th Jun 2014 16:09

Info from Luke Schiada - Senior NTSB Investigator in charge of N121JM investigation.

tempilot 4th Jun 2014 16:17

Gulfstream IV in Bedford MA
 
Thanks Feathered and Robbreid. T.

satpak77 4th Jun 2014 16:20

According to this, crew called "rotate" and after that point, control issues possibly came into play. Simplistically, I wonder if after rotation, the aircraft failed to rotate (for whatever reason)

Plane?s brake pressure rose before Hanscom crash, data show - Metro - The Boston Globe



BEDFORD — The Gulfstream IV jet that crashed at Hanscom Field Saturday night, killing seven people, reached a speed of 190 miles per hour before slowing down during its attempted takeoff and hurtling into a gully, air crash investigators said Tuesday.

Information from the plane’s flight data recorder indicated that the jet’s thrust reversers had been turned on and that brake pressures were rising, Luke Schiada, the lead investigator for the National Transportation Safety Board, said at the scene.

The scenario described by the investigator suggested that the pilots were trying to abort the takeoff, one veteran pilot said. Thrust reversers are typically used to slow planes down by diverting jet exhaust to the front, rather than the back, as in normal operation.
Related
Photos
6/01/2014 - Bedford, MA - Hanscom Air Force Base Civil Air terminal - Frank McGinn, cq right, with the Massachusetts State Police, and Gary Coffey, cq, left, with the FBI, were on site at Hanscom Air Force Base the morning after a fatal plane crash that killed 7 people, including the co-owner of the Philadelphia Enquirer. Members of the media waited on Sunday morning for updates regarding a fatal plane crash at Hanscom Air Force Base that took place on the night before on May 31, 2014. Dina Rudick/Globe Staff.
Photos: Crash at Hanscom

Data, voice recorders recovered
Video: Hanscom jet crash
Audio: 911 calls after the crash

“The thrust reversers deployed and the wheel brake pressures rose as the airplane decelerated,” Schiada said. “We’re also observing tire marks on the runway.”

Schiada declined to say outright that the pilots were trying to stop the plane, saying: “We’re not interpreting the information that the thrust reversers were deployed. . . . I don’t want to interpret what the actions are.”

He also did not give any indication as to why the crew might have been trying to stop the plane.

“We’re not going to speculate,” Schiada said.

However, Bruce Landsberg, an experienced pilot and president of the Aircraft Owners and Pilots Association Foundation in Frederick, Md., said it sounded as though the pilots had decided to halt the plane.

It appeared, he said, that “the crew, for whatever reason, decided they needed to reject the takeoff, and they ran out of runway before they got the airplane stopped.”

As it raced down the runway, the airplane reached a maximum speed of about 165 knots, or about 190 miles per hour, Schiada said. But the flight data recorder indicated it never left the ground.

The flight recording ends about seven seconds after the thrust reversers were deployed. At that point, the plane had slowed to about 100 knots, or 115 miles per hour, Schiada said.

In addition, the jet’s cockpit voice recorder captured various callouts in the cockpit, including “rotate,” as the plane sped down the runway. That is typically the signal from the copilot to the pilot to pull back on the control yoke and bring the nose up, Landsberg said.

“After the rotate callout, the [cockpit voice recorder] captured comments concerning aircraft control,” Schiada said.

The NTSB investigator would not elaborate on what those comments were.

Schiada said the cockpit voice recording ultimately ended with the sound of impact.

On Monday, investigators recovered the two recorders. Schiada stressed that the analysis of the data from the recorders was preliminary “and we still have a great deal of work to do.”

He said both devices had captured hours of data, including the final 49 seconds of the flight when the plane began to roll down the runway and then crashed.

According to Schiada, the cockpit voice recorder had captured about two hours of “good to excellent” audio, while the flight data recorder had captured about 41 hours of data. Both devices were made by L-3 Communications.

The plane was taking off at about 9:40 p.m. Saturday, heading to Atlantic City, N.J., with Lewis Katz, 72, co-owner of the Philadelphia Inquirer, aboard, as well as three of his guests and a three-member crew.

NTSB officials have said the plane left the end of the official runway, which is 7,011 feet long, traveled another 1,000 feet over extra paved surface, and then another 819 feet on the grass before hurtling into a gully at the edge of the airport, where it was consumed by flames.

Along the way, the Gulfstream IV destroyed an antenna used to guide planes on instrument landing approaches, as well as a chain-link fence, investigators have said.

The crew members aboard the plane were: pilot James McDowell, 51, of Georgetown, Del.; copilot Bauke “Mike” De Vries, 45, of Marlton, N.J.; and flight attendant Teresa Ann Benhoff, 48, of Easton, Md.

Katz’s guests were Anne Leeds, a retired preschool teacher from Longport, N.J.; Marcella Dalsey, executive director of the Drew A. Katz Foundation; and Susan K. Asbell, who served with Dalsey on the strategic planning committee of the Boys & Girls Club of Camden County, N.J.

Investigators expect to remain at the crash site gathering information through the end of the week, Schiada said. A preliminary report on the crash is expected to be issued by the agency next week.

In the meantime, Schiada said, investigators will continue reviewing information about the flight crew, witness statements, and surveillance footage, among other evidence. The recorders have been forwarded to NTSB labs in Washington, D.C.

Schiada said that investigators had not found any problems with the plane’s brakes or tires and that authorities were also reviewing the configuration of the flaps at takeoff.

Investigators have not had a chance to examine the engines yet, he said.

Bruce “Buck” Rodger, president of the Los Angeles-based Aero Consulting Experts, said a number of factors may have contributed to the crash.

“There’s always a buildup to a reason why an airplane has crashed,” Rodger said. “There will be more than one event here, absolutely.”


robbreid 5th Jun 2014 00:01

They stated the FDR indicated the thrust reversers has deployed 7 seconds before the cvr stopped recording - the impact sound was heard - just a note that the wreckage shows the reversers stowed ?

Jet Jockey A4 5th Jun 2014 11:30

@ fantycloud...
 
"compare news coverage to this accident vs the aspen crash.... Is it a coincidence that it was a newspaper boss that perished? I want to know about the accident and the news sites are sush.... guess we wait for NTSB report."

I believe the fact that other jets waiting for takeoff in Aspen saw the accident live and indeed took pictures and videos as it happened help the Aspen crash make more news.

Also there were IIRC 4 airport camera videos published showing the whole crash as it happened.

Jet Jockey A4 5th Jun 2014 11:36

Too early to know what happened in this crash and I don't want to speculate but this accident reminds me of the Challenger 600 crash in Teterborro.

Both very high speed rejects where the aircraft failed to get airborne because of some sort of issue.

Of course now we know the reasons behind that Challenger crash, and wonder if something similar happened here. Could a G IV be loaded in such a way as to prevent a normal rotation at Vr?

tlbrown350 5th Jun 2014 14:23

Anyone familiar with the GIV before T/O control lock procedures.

Malfunctioning Flight-Control System Likely Led to Lewis Katz Jet Crash - WSJ

JRBarrett 5th Jun 2014 14:30


Originally Posted by Jet Jockey A4 (Post 8508666)
Too early to know what happened in this crash and I don't want to speculate but this accident reminds me of the Challenger 600 crash in Teterborro. Both very high speed rejects where the aircraft failed to get airborne because of some sort of issue. Of course now we know the reasons behind that Challenger crash, and wonder if something similar happened here. Could a G IV be loaded in such a way as to prevent a normal rotation at Vr?

I can't think of any operational load-out of a GIV that would produce a fwd CG so far out of limits that the aircraft would be unable to rotate. It is a completely different design than the Challenger 600, which

On a GIV, one would have to load many hundreds of pounds of cargo in the forward entrance corridor to move the fwd CG out of limits. Not something likely to be done in a high-end executive jet.

The fuel and pax load of the Challenger at TEB put them over gross, and out of CG limits.

The GIV has a max fuel capacity of 29,500 pounds. They probably had less than half of that for the short hop from BED to ACY, and with just 4 pax, it stands to reason that they were loaded well within the normal envelope.

I'm pretty sure that this accident was the result of some sort of major failure in the flight control system - but I will leave it to the on-scene NTSB and manufacturer's investigators to determine the exact nature of the failure. Because of the massive destruction of the airframe from the impact and fire, that investigation may take quite some time.

Feathered 5th Jun 2014 15:19

What kind of flight control systems check would be on the preflight checklist? Are the flight controls even visible from the G IV cockpit?

znightflyer 5th Jun 2014 17:27

Anybody have a link to the series of picture that were posted...seems the link is not valid anymore

mutt 5th Jun 2014 17:42


What kind of flight control systems check would be on the preflight checklist?
Release the control lock prior to start.
Check Stall Barrier after start
Check ground spoilers
Check flight controls, wings can be seen using window mounted mirrors.

Bill Harris 5th Jun 2014 18:22


Anybody have a link to the series of picture that were posted...seems the link is not valid anymore
It's still good:

Photos: Crash at Hanscom (Photo 1 of 37) - Pictures - The Boston Globe

and they seem to have revised the photos (different # of photos).

Astra driver 5th Jun 2014 18:23

The GIV like all other Gulfstream models is very easy to keep within CG limits, a Pax load of 4 would almost certainly be within CG limits regardless of where they sat within the cabin, and so long as one starts within the CG envelope it is impossible to take on a fuel load that would shift you outside of it.

As far as control checks go, in recent years a "Bungee check" of the elevator controls was added to the line-up checklist for legacy Gulfstream models (G2 through G5) which involves pulling the control column full aft and then releasing to ensure it falls full forward with no bounce. Not sure if all crews are complying with this though.


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