1. A wireless transmit/receive unit (WTRU) comprising:a transmitter; and
a processor configured to:
activate a timer;
transmit, via the transmitter, a dedicated non-contention based random access channel (RACH) preamble to attempt RACH access prior to an expiration of the timer; and
transmit, via the transmitter, a contention-based RACH preamble after the RACH access attempt fails using the dedicated non-contention based RACH preamble and after the expiration of the timer.