An H25B crew, upon landing at lvk, experienced violent shaking of the aircraft, a result of the 2 le...

Attributes
ACN	541825
Time
Date	200203
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : luk.airport
State Reference	CA
Altitude	agl single value : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : bur.tower
Operator	common carrier : air carrier
Make Model Name	HS 125 Series 700
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	landing : roll
Flight Plan	VFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : multi engine pilot : cfi
Experience	flight time last 90 days : 30 flight time total : 6000 flight time type : 600
ASRS Report	541825
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other flight crewa other flight crewb
Resolutory Action	none taken : anomaly accepted other
Consequence	other other other
Supplementary
Problem Areas	Company Flight Crew Human Performance Aircraft Maintenance Human Performance
Primary Problem	Aircraft

Narrative:

During a part 91 ferry leg a normal landing was made on runway 25R at lvk. Very shortly after touchdown and prior to brake application, the aircraft began to shake violently and veer to the left. Control was maintained and the aircraft was brought to a stop on the ramp. Upon investigation, it was found that both main gear tires on the left gear leg had burst and disintegrated. Our maintenance department conferred with technical representatives from raytheon who offered the scenario of contamination of the brake control unit on the gear causing the brakes to have a slight amount of brake pressure at touchdown. The skid marks on the runway and the recovered tire pieces show this to be the case. Most aircraft anti-skid system have what is commonly referred to as locked wheel protection. What that means is the brake system will not allow the wheels to touch down and have brake pressure on them. The brake system on a hawker is slightly different. The antiskid system is completely mechanical and requires no electrical power to operate but it has no locked wheel protection for touchdown. In the past it was a before landing checklist item to step on the brake peddles and note the pressure drop. A few yrs ago, raytheon sent out a bulletin telling operators to stop this practice since it was possible for the brake pressure to not fall to zero or a brake to freeze to a wheel, and since there was no locked wheel protection at touchdown the tire would burst. Raytheon removed the checklist item from flight manuals and checklists. Our company correspondingly removed the brake check from our checklist to conform to the manufacturer's checklist. The problem is now you never look at the brake pressure gauge and you would never know if there was any pressure on the brakes. As a company we are considering adding a checklist item in the before landing checklist of brake pressure-confirm zero.

Original NASA ASRS Text

Title: AN H25B CREW, UPON LNDG AT LVK, EXPERIENCED VIOLENT SHAKING OF THE ACFT, A RESULT OF THE 2 L MAIN TIRES BURSTING ON TOUCHDOWN.

Narrative: DURING A PART 91 FERRY LEG A NORMAL LNDG WAS MADE ON RWY 25R AT LVK. VERY SHORTLY AFTER TOUCHDOWN AND PRIOR TO BRAKE APPLICATION, THE ACFT BEGAN TO SHAKE VIOLENTLY AND VEER TO THE L. CTL WAS MAINTAINED AND THE ACFT WAS BROUGHT TO A STOP ON THE RAMP. UPON INVESTIGATION, IT WAS FOUND THAT BOTH MAIN GEAR TIRES ON THE L GEAR LEG HAD BURST AND DISINTEGRATED. OUR MAINT DEPT CONFERRED WITH TECHNICAL REPRESENTATIVES FROM RAYTHEON WHO OFFERED THE SCENARIO OF CONTAMINATION OF THE BRAKE CTL UNIT ON THE GEAR CAUSING THE BRAKES TO HAVE A SLIGHT AMOUNT OF BRAKE PRESSURE AT TOUCHDOWN. THE SKID MARKS ON THE RWY AND THE RECOVERED TIRE PIECES SHOW THIS TO BE THE CASE. MOST ACFT ANTI-SKID SYS HAVE WHAT IS COMMONLY REFERRED TO AS LOCKED WHEEL PROTECTION. WHAT THAT MEANS IS THE BRAKE SYS WILL NOT ALLOW THE WHEELS TO TOUCH DOWN AND HAVE BRAKE PRESSURE ON THEM. THE BRAKE SYS ON A HAWKER IS SLIGHTLY DIFFERENT. THE ANTISKID SYS IS COMPLETELY MECHANICAL AND REQUIRES NO ELECTRICAL PWR TO OPERATE BUT IT HAS NO LOCKED WHEEL PROTECTION FOR TOUCHDOWN. IN THE PAST IT WAS A BEFORE LNDG CHKLIST ITEM TO STEP ON THE BRAKE PEDDLES AND NOTE THE PRESSURE DROP. A FEW YRS AGO, RAYTHEON SENT OUT A BULLETIN TELLING OPERATORS TO STOP THIS PRACTICE SINCE IT WAS POSSIBLE FOR THE BRAKE PRESSURE TO NOT FALL TO ZERO OR A BRAKE TO FREEZE TO A WHEEL, AND SINCE THERE WAS NO LOCKED WHEEL PROTECTION AT TOUCHDOWN THE TIRE WOULD BURST. RAYTHEON REMOVED THE CHKLIST ITEM FROM FLT MANUALS AND CHKLISTS. OUR COMPANY CORRESPONDINGLY REMOVED THE BRAKE CHK FROM OUR CHKLIST TO CONFORM TO THE MANUFACTURER'S CHKLIST. THE PROB IS NOW YOU NEVER LOOK AT THE BRAKE PRESSURE GAUGE AND YOU WOULD NEVER KNOW IF THERE WAS ANY PRESSURE ON THE BRAKES. AS A COMPANY WE ARE CONSIDERING ADDING A CHKLIST ITEM IN THE BEFORE LNDG CHKLIST OF BRAKE PRESSURE-CONFIRM ZERO.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

An H25B crew, upon landing at lvk, experienced violent shaking of the aircraft, a result of the 2 left main tires bursting on touchdown.