Clearing with TIS or TCAD

Source: www.pilotworkshop.com
Featuring Bob Nardiello

Subscriber question:

"I have a hard time spotting aircraft when looking outside the aircraft. Can I use my TIS or TCAD to clear before making a turn to a new heading?" - Brent A.

Bob:

"No. Using these devices in lieu of visually clearing the area is a dangerous practice which creates a collision hazard. These devices display only traffic with an operating transponder. Aircraft without a transponder, such as a glider, won't appear.

TIS simply transmits what ground-based, approach-control type radar sees. If you are below coverage or outside of the coverage, your TIS device won't indicate traffic.

TCAD relies on another aircraft's transponder sending you a reply. Many TCAD systems are passive in that they don't interrogate other aircraft transponders and instead rely upon center or approach radar or an active TCAD or TCAS system to do the interrogating. There are additional limitations to the performance of these devices as well. Review the operating manual for these devices.

Active collision avoidance requires a constant search of the air around your aircraft to identify others in close proximity. A thorough look visually under and over the wings of your aircraft is what's required before making a turn."