Incident Summary
While flying in precipitation deviating within 10 miles from the edge of a level 5 thunderstorm associated with a squall line, the airplane was struck by lightning. The strike caused arcing damage to the No. 1 elevator pressure and No. 2 elevator return hydraulic lines, leading to depletion of hydraulic fluid from the Nos. 1 and 2 hydraulic system reservoirs.
Damage and Sequence
After the lightning strike, the airplane continued to its destination and landed on a wet runway. Following touchdown, two of the four main landing gear tires ruptured. The airplane then traveled off the left side of the runway, across grass, and came to rest with the nose landing gear separated.
System Findings
A loose canon plug at the parking brake shutoff valve was discovered, which prevented the operation of the alternate antiskid system. That area had been inspected two days earlier. The airplane was only equipped by design with one bonding strap located on the left side of the airplane for the horizontal and vertical stabilizer, which failed. Advisory Circular recommends that the area be designated for carrying substantial amounts of electrical current, but the airplane was not designed for such.
Weather and Training
The flight crew was not provided convective sigmets for the central U.S., which indicated severe thunderstorms over Birmingham. The destination airport was near the boundary of the east and central regions for convective sigmets. The airline does not conduct weather radar training in recurrent, upgrade, or requalification training. The dispatcher did not provide to the flight crew weather watches that were available 15 minutes before and after the flight departed.