Yes, If you just want to delete the static IP address (& leave the controller address learnt by AP as it is) then you can use the below two lines. You cannot do write mem as it is CAPWAP AP.
clear capwap ap ip address
clear capwap ap ip default-gateway
If you do the below, it won't remove statically configured IP, So it won't achieve what you want.
"clear capwap private-config"
If you want to delete everything (even previously known controller IP from AP NVRAM) you can do this
AP0026.0b63.caf4#debug capwap console cli
This command is meant only for debugging/troubleshooting
Any configuration change may result in different
behavior from centralized configuration.
CAPWAP console CLI allow/disallow debugging is on
AP0026.0b63.caf4#erase /all nvram:
Erasing the nvram filesystem will remove all files! Continue? [confirm]
[OK]
Erase of nvram: complete
*Mar 1 00:05:19.793: %SYS-7-NV_BLOCK_INIT: Initialized the geometry of nvramoad
AP0026.0b63.caf4#reload
Below reference should be useful on this
https://supportforums.cisco.com/docs/DOC-24917
HTH
Rasika
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