remarks section of the flight plan when requesting tower en route control. 

d. All approach controls in the system may not operate up to the maximum TEC altitude of 10,000 feet. IFR flight may be planned to any satellite airport in proximity to the major primary airport via the same routing. 

## 4 − 1 − 20. Transponder and ADS − B Out Operation 

## a. General 

1. Pilots should be aware that proper application of transponder and ADS − B operating procedures will provide both VFR and IFR aircraft with a higher degree of safety while operating on the ground and airborne. Transponder/ADS − B panel designs differ; therefore, a pilot should be thoroughly familiar with the operation of their particular equipment to maximize its full potential. ADS − B Out, and transponders with altitude reporting mode turned ON (Mode C or S), substantially increase the capability of surveillance systems to see an aircraft. This provides air traffic controllers, as well as pilots of suitably equipped aircraft (TCAS and ADS − B In), increased situational awareness and the ability to identify potential traffic conflicts. Even VFR pilots who are not in contact with ATC will be afforded greater protection from IFR aircraft and VFR aircraft that are receiving traffic advisories. Nevertheless, pilots should never relax their visual scanning for other aircraft. 

2. Air Traffic Control Radar Beacon System (ATCRBS) is similar to and compatible with military coded radar beacon equipment. Civil Mode A is identical to military Mode 3. 

3. Transponder and ADS-B operations on the ground . Civil and military aircraft should operate with the transponder in the altitude reporting mode (consult the aircraft’s flight manual to determine the specific transponder position to enable altitude reporting) and ADS − B Out transmissions enabled at all airports, any time the aircraft is positioned on any portion of the airport movement area. This includes all defined taxiways and runways. Pilots must pay particular attention to ATIS and airport diagram notations, General Notes (included on airport charts), 

and comply with directions pertaining to transponder and ADS-B usage. Generally, these directions are: 

(a) Departures.  Select the transponder mode which allows altitude reporting and enable ADS-B during pushback or taxi-out from parking spot. Select TA or TA/RA (if equipped with TCAS) when taking the active runway. 

(b) Arrivals.  If TCAS equipped, deselect TA or TA/RA upon leaving the active runway, but continue transponder and ADS − B transmissions in the altitude reporting mode. Select STBY or OFF for transponder and ADS − B upon arriving at the aircraft’s parking spot or gate. 

## 4. Transponder and ADS-B Operations While Airborne. 

(a) Unless otherwise requested by ATC, aircraft equipped with an ATC transponder main- tained in accordance with 14 CFR Section 91.413 MUST operate with this equipment on the appropriate Mode 3/A code, or other code as assigned by ATC, and with altitude reporting enabled whenever in controlled airspace. If practicable, aircraft SHOULD operate with the transponder enabled in uncontrolled airspace. 

(b) Aircraft equipped with ADS − B Out MUST operate with this equipment in the transmit mode at all times, unless otherwise requested by ATC. 

(c) When participating in a VFR formation flight that is not receiving ATC services, only the lead aircraft should operate their transponder and ADS − B Out. All other aircraft should disable transponder and ADS − B transmissions once established within the formation. 

## NOTE − 

If the formation flight is receiving ATC services, pilots can expect ATC to direct all non − lead aircraft to STOP SQUAWK, and should not do so until instructed. 

5. A pilot on an IFR flight who elects to cancel the IFR flight plan prior to reaching their destination, should adjust the transponder/ADS − B according to VFR operations. 

6. If entering a U.S. OFFSHORE AIRSPACE AREA from outside the U.S., the pilot should advise on first radio contact with a U.S. radar ATC facility that such equipment is available by adding “transponder” or “ADS − B” (if equipped) to the aircraft identification. 

