Date: 202101
Local time of day: 0001-0600
Location: ZZZZ.Airport, FO
Flight conditions: IMC
Aircraft: Commercial Fixed Wing
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Human factors: Troubleshooting; Other / Unknown; Situational Awareness; Fatigue
Anomaly: No Specific Anomaly Occurred All Types
Detector: Person Flight Crew
When detected: Other All
Result: General None Reported / Taken
Contributing factors: Company Policy; Human Factors; Environment - Non Weather Related
Primary problem: Ambiguous

Narrative: First leg arrives ZZZZ mid evening; and crew arrives hotel at approximately close to midnight; after a 13-hour duty all-nighter; rests until van departure the next evening ZZZZ time ; for a report time 2 hours later and a 2-leg 14:20 duty day with 10+ hours of flying to ZZZZ1 and back followed by another 1.5-2 hours to get back to the ZZZZ hotel. With a 3-person crew; and the FAR117 limitations; the ZZZZ1 turn begins with no one properly rested (due to the 3-person crew; each crewmember gets at most 3 hours of rest on the red-eye to ZZZZ on the first night; and arrives at hotel just after Window of Circadian Low (WOCL); unable to get much restorative rest. The next night's report time is at the *beginning* of the WOCL; meaning two nights in a row of disrupted sleep (unrelated to the ZZZZ1 turn; but indicative of the poorly-built nature of this trip; the third duty period of the 5-day pairing also includes a redeye; for a total of 3 min-rest 3-pilot redeyes in 5 days). Concerning the ZZZZ-ZZZZ1-ZZZZ legs; because of the 117 restrictions; depending how the Relief Pilot (RP)  and PM split the first leg or part of the 2nd; and the expected flight time of the ZZZZ-ZZZZ1 leg; no one gets decent rest. In our pairing; I as the RP slept first on the outbound leg for 2 hours; and the PM slept next for 3; and the PF slept the entire return leg (2.5 hrs). This was FAR117 compliant; but due to pairing construction is essentially too little; at the wrong time; and contributed to a degradation in safety. It is not helped by a 2-hour ground sit (during which it's impossible to rest because the countries authorities enter the airplane for a security sweep and postflight / preflight duties must be accomplished; and the constant loud noises and aircraft motion from cargo loading/unloading). So the RP and PM sleep a very small amount during the WOCL; and the PF doesn't get a rest opportunity until after the WOCL; when it may no longer be possible to sleep.This is bananas. ZZZZ1; and the country's airspace in general; is among our more challenging operations (language; altimetry; nonstandard ATC phraseology and procedures; night/weather; unfamiliarity with fix names; etc.). Setting up a minimum crew with back-to-back red eyes and little rest opportunity in that environment is dangerous. And the crew is then left to consider a fatigue call on the ground in ZZZZ1 - one of the worst places in the world to stop the operation for crew and airline alike.




Synopsis: Air carrier First Officer reported this crew rotation/pairing is not safe due to a fatigue factor.