Wednesday, April 11, 2012

Old Wounds

The National Transportation Safety Board held a press conference in Reno, NV Tuesday to make seven safety recommendations for the Reno Air Races.

Though the investigation of the fatal September 2011 Galloping Ghost accident is ongoing, the NTSB did provide some details of their line of inquiry, a timeline of the accident and some photo and video evidence.

NTSB Chair Deborah Hersman Reno Gazette-Journal Photo
I watched the presser LIVE on the internet. The Reno paper has the story, and linked to the live stream.

The language in the Gazette-Journal's story was a little less than precise, so I'll add my two cents:

NTSB Chair Deborah Hersman said:
“Our investigation revealed that this pilot in this airplane had never flown at this speed on this course,” . “We are issuing a safety recommendation to ensure that pilots and their modified airplanes are put through their paces prior to race day.”

On the second page of the RGJ's web story Reno Air Racing Association CEO Mike Houghton said he questioned the NTSB’s statement that Leeward had never flown his aircraft at top speed on that course. He said Leeward likely went faster during the qualifying rounds, when the course was wide open.

The gap here between the NTSB's statement and the rebuttal is a little too wide to dispel misconceptions in my opinion. Every casual reader who didn't click thru to page two takes it as fact that Jimmy Leeward had "never flown this airplane had never flown at this speed on this course." Intentional or not, this is inexcusable spin (sorry, no pun intended)

"After the hearing, Howard Plagens, the lead NTSB investigator, detailed the sequence of events that led to the crash, which took about 6 seconds from the start of the problems."

"The Galloping Ghost was banking left at about a 70-percent around the last pylon when it suddenly banked about 90 percent, he said. The maximum G-force likely hit about 1.5 seconds after “the upset,” he said. The aircraft then rolled right and over, he said, and that’s when the elevator trim tab fell off the tail."

"That description does not fit with speculation made by many aviation experts, who said they believed the plane went out of control after the trim tab fell off."

"Plagens said it was clear from photos and video that the trim tab’s failure occurred well after the plane went out of control. NTSB investigators are still trying to determine what caused the initial “upset,” he said."

Again this is very un-precise language here. I'll break it down with my notes.

"The Galloping Ghost was banking left at about a 70-percent around the last pylon when it suddenly banked about 90 percent, he said."

The sudden banking is "the upset", and precipitated the radical pull-up that caused the G-forces to hit maximum 1.5 seconds later. The Chair said there was telemetry from the Ghost, and that the on-board accelerometer recorded the spike in G-load, but was only capable of recording 9G, and this event went past that scale.

NTSB Chair Deborah Hersman said the NTSB is working on the peak G readings.

The photos and videos showed the failure of the elevator trim tab caused the upset. I surmise it was a failure of the control linkage at speed that allowed the trim tab to loose it's purchase on the airflow over the elevator causing the severe pull-up that caused Leeward to black out. Photos shown by the NTSB show Jimmy slumped forward and to the right in the cockpit as the Ghost was rolling to the right over the top into the fatal dive.

It was near the top that the failed elevator trim tab departed the aircraft. Though the videos don't have the resolution necessary to show it, the trim tab, from "the upset", now unattached to it's control rod, was free to flutter at high speed until it broke up and departed the aircraft.

The NTSB displayed photos of the trim tab at each stage of the failure process, from normal before "the upset", deflecting at the beginning of the pull-up, and leaving the aircraft at the top of the roll. The photos are telling.

The rest of the recommendations are sound, common sense ideas.

The NTSB recommends increasing the distance between the flight line and spectators be increased from 500ft to 1000ft. Their map of the Stead Field flight line and the grandstands showed September's distance to be 815ft, and 750ft to the pits. Very doable for September's Air Races.

G-force training for Unlimited Class pilots, and perhaps mandated G-suits for Unlimited pilots are a step in the right direction. I'm sure G-suit systems are very expensive, and probably fairly heavy. Jet aircraft carry these G-suit systems with their plumbing and compressors.

Aircraft inspections and record keeping upgrades are in order as well.

You can watch the video of today's press conference in Flash here. And in WMV here.

I don't see any of the seven recommendations as game changers. I'm confident that RARA will comply and the Reno National Championship Air Races will continue. The only potential stumbling block I see might be the insurance premiums for the event.

Though I wasn't present in Stead that awful day last September, I can't wait to see and hear the Unlimiteds again, if only to begin to erase those grisly memories.

Godspeed Jimmy Leeward, I hope the Reno Air Races will continue as just a part of your legacy.

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