Time to change disk?

I really seem to be having bad luck with unRaid. Recently a lightning strike cut the power while the server was running. When I next booted up, it ran a parity check - everything was fine. When I started it up again today, I found that Disk 11 was giving me some errors and writing to the array was impossible.

I've attached the syslog (running 4.5.1) in the hope that someone can confirm whether it's "only" a disk problem or if there's some other issue that I should be concerned about. Btw, hardware is a Supermicro board C2-SEE, PSU is a Seasonic X Series 650W and Disk 11 is a WD 1.5GB SATA disk. When  I first got the problem I shut down and checked that the cables to Disk 11 were not loose, so I don't think it's a loose cable problem.

Here are some of what I think are the relevant lines:

Apr 28 20:04:44 Tower kernel:          res 51/40:00:17:de:09/00:00:00:00:00/f6 Emask 0x9 (media error)

Apr 28 20:04:44 Tower kernel: ata1.01: status: { DRDY ERR }

Apr 28 20:04:44 Tower kernel: ata1.01: error: { UNC }

Apr 28 20:04:47 Tower kernel: ata1.00: configured for UDMA/133

Apr 28 20:04:50 Tower kernel: ata1.01: configured for UDMA/133

Apr 28 20:04:50 Tower kernel: ata1: EH complete

Apr 28 20:04:53 Tower kernel: ata1.01: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0

Apr 28 20:04:53 Tower kernel: ata1.01: cmd c8/00:08:17:de:09/00:00:00:00:00/f6 tag 0 dma 4096 in

Apr 28 20:04:53 Tower kernel:          res 51/40:00:17:de:09/00:00:00:00:00/f6 Emask 0x9 (media error)

Apr 28 20:04:53 Tower kernel: ata1.01: status: { DRDY ERR }

Apr 28 20:04:53 Tower kernel: ata1.01: error: { UNC }

Apr 28 20:04:55 Tower kernel: ata1.00: configured for UDMA/133

Apr 28 20:05:00 Tower kernel: ata1.01: configured for UDMA/133

Apr 28 20:05:00 Tower kernel: sd 1:0:1:0: [sdb] Unhandled sense code

Apr 28 20:05:00 Tower kernel: sd 1:0:1:0: [sdb] Result: hostbyte=0x00 driverbyte=0x08

Apr 28 20:05:00 Tower kernel: sd 1:0:1:0: [sdb] Sense Key : 0x3 [current] [descriptor]

Apr 28 20:05:00 Tower kernel: Descriptor sense data with sense descriptors (in hex):

Apr 28 20:05:00 Tower kernel:        72 03 11 04 00 00 00 0c 00 0a 80 00 00 00 00 00

Apr 28 20:05:00 Tower kernel:        06 09 de 17

Apr 28 20:05:00 Tower kernel: sd 1:0:1:0: [sdb] ASC=0x11 ASCQ=0x4

Apr 28 20:05:00 Tower kernel: end_request: I/O error, dev sdb, sector 101309975

Apr 28 20:05:00 Tower kernel: ata1: EH complete

Apr 28 20:05:00 Tower kernel: md: disk11 read error

Apr 28 20:05:00 Tower kernel: handle_stripe read error: 101309912/11, count: 1

I did try spinning up all the drives and also telnetting in, which might explain some other things seen in the log.

syslog.zip