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Pilot training guides for egca dgca cpl atpl in India

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The Role of FDTL in management of Pilot fatigue

A simple explainer of the FDTL rules that governs a pilot’s working hours in India



Latest DGCA FDTL norms were released last month, here's what the buzz was about - https://www.wingmanlog.in/post/6-things-you-need-to-know-from-dgca-fdtl-press-release



What do you understand by the words Pilot Fatigue?


Fatigue in aviation refers to a condition where pilots or crew members experience decreased mental or physical performance because of various factors like lack of sleep, working for long hours without breaks, or working during times when their body naturally wants to rest (like overnight shifts). This reduced performance can make it harder for them to stay alert and safe while operating an aircraft or performing important safety tasks. Essentially, it's like feeling really tired and not being as sharp or focused as usual, which can be risky when flying a plane or ensuring passengers' safety.  ICAO mandates that the state of the operator establishes regulations to address Fatigue management. The State shall establish prescriptive regulations for Flight Time, Flight Duty Period, Duty Period and Rest Period Limitations and, if authorizing the operator to use a Fatigue Risk Management System (FRMS) to manage fatigue, establish FRMS Regulations


Don’t have time to read the whole post? just slide through the latest changes to the FDTL





What is FDTL ?

The flight duty time limitations (FDTL) are laid down by the Directorate-General of Civil Aviation (DGCA) to ensure adequate rest timings for pilots and flight attendants and prevent fatigue-related safety issues.


Duty : Any duty assigned by the operator to flight crew members, such as flying, administrative tasks, training, positioning, and standby, which could potentially cause fatigue


Duty Period :

A duty period begins when a flight crew member starts duty as required by the operator and ends when they are relieved of all duties. Flight Duty Period (FDP) : A duty period for a flight crew member begins when they report for duty and ends when the last flight they're involved in ends with engine shutdown.*Flight Time (FT): Flight time is the duration from an aircraft's initial movement for takeoff until it comes to a complete stop at the end of the flight, also known as "block-to-block" or "chocks-to-chocks" time.


Acclimatized : Crew members are considered acclimatized to departure time zones for the first 48 hours if there's a significant time zone difference. After this period, they adjust to local time zones for subsequent duties. This affects calculations for maximum daily flight duty periods to ensure crew members' alertness and safety


What do you understand by WOCL (Window of Circadian Low)?

It is that period of the night when the human body is at the lowest trough of performance. This estimate of the window is calculated from scientific data on the circadian low of performance, alertness, subject report (i.e. peak fatigue) and body temperatureWOCL means a period between 0200h and 0600h in the time zone to which a crew member is acclimatized.


What is the AIM of the FDTL :


It aims to restrict the number of hours a flight crew can do in a specified period. There are daily, monthly, weekly and annual limits. There are limits on flight duty based on whether duty encompasses night or WOCL periods. It also limits total flight duty time based on the number of planned landings.Here’s  quick reference  tables for the allowed flight time, duty period and number of landings  allowed for two crew operations and augmented crew operations. 


MAXIMUM CUMULATIVE FLIGHT TIME AND DUTY PERIOD LIMITATIONS:-



FLIGHT TIME, FLIGHT DUTY PERIOD AND DUTY PERIOD LIMITS: TWO PILOT OPERATION



FLIGHT TIME AND FLIGHT DUTY PERIOD LIMITS: AUGMENTED CREW




Let’s check how much you know about the FDTL rules now




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