How to read your FAR 117 rolling windows
The Part 117 section of the dashboard shows five rolling-window cards. Each card is a fact, citing a §117 paragraph. None of the cards renders a legality verdict. This guide walks through each card, what the number means, and what to do if a card shows pressure.
Why this matters
The five windows are how Part 121 schedulers, dispatchers, and individual pilots track time pressure across a month. Knowing which window is closest to its limit helps you plan the next 7 to 30 days of trips. DaPilot shows the same numbers your operator's scheduling system uses, but for your personal awareness.
The five windows
1. §117.23(b)(1): Flight time, 672 hours
Limit: 100 hours of flight time in any 672-hour rolling window.
The 672-hour window is approximately 28 days. The card reads:
Flight time (672 hr): 61.4 / 100, §117.23(b)(1)
Tap to see every flight contributing to the 61.4 figure. The list is dated; the oldest flight in the window is the one whose hours will drop off first as the window rolls forward.
2. §117.23(b)(2): Flight time, 365 days
Limit: 1,000 hours of flight time in any 365-day rolling window.
The annual cap. For most line pilots this is the slowest-rolling window: it changes by hours per week, not by trip. The card matters most for high-credit pilots flying 80+ hours a month who need to plan a year-end fade.
3. §117.23(c)(1): FDP, 168 hours
Limit: 60 hours of FDP duration in any 168-hour rolling window.
The week's duty cap. The 168-hour window is 7 days. FDPs include report time, taxi-only time, gate delays, and so on, all of which count even though they don't add to flight time. Many domestic pilots cap out here before they cap out on flight time.
4. §117.23(c)(2): FDP, 672 hours
Limit: 190 hours of FDP duration in any 672-hour rolling window.
The 28-day duty cap. Same trend as 60/168: pressure here is duty-driven, not flight-driven. Often the closest cap to the limit on a heavy month.
5. §117.25: Weekly mandatory rest
Requirement: at least 30 consecutive hours of rest in any 168-hour rolling window.
This card is binary in concept: have you had a 30+ hour rest in the previous 168 hours, or not? In DaPilot it shows the longest single rest in the window. If that rest is 30+ hours, the card is satisfied. If not, you see the gap.
Reading pressure
Cards visually indicate pressure based on percentage of the cap.
| Pressure | Color | Range | What it means |
|---|---|---|---|
| Safe | Muted teal | 0 to 69% | Card recedes; no immediate planning concern |
| Pressure | Amber | 70 to 89% | Card draws the eye; consider the next 7-14 days |
| Heavy pressure | Red | 90% and above | Card stands out; think before accepting more flying |
Colors are personal pressure indicators, not legality verdicts. The pilot is the decider per the regulatory disclaimer.
What to do when a card shows pressure
If a card is amber or red, tap to see the inputs. The contributing list shows the flights or FDPs feeding the value, oldest first.
The oldest item is the next to drop off. Subtract its hours from the window total once it drops. That gives you "expected hours after the window rolls."
For example: §117.23(c)(1) (FDP in 168 hours) shows 55 / 60. The oldest FDP in the window is a 6-hour duty period from 6 days ago. Tomorrow at the same time, that FDP rolls out. Your post-rollover total is 49, leaving 11 hours of duty capacity. Whether you accept a trip the next day depends on the trip's FDP length and your other windows.
This kind of forward-looking math is why the dashboard is structured around drilling into a card; the answer to "can I take this trip" is rarely a single number.
Acclimation and Appendix B max FDP
The five rolling windows are independent of Appendix B. Appendix B governs the maximum FDP for a single duty period, not cumulative time. The Appendix B max for your current FDP shows on the FDP card itself, with the report time and segment count feeding the lookup.
Acclimation affects Appendix B (different table column based on acclimation state) but not the rolling windows.
If your acclimation state changes during a rotation (you've been in Tokyo long enough to acclimate), set it on the next FDP. The Appendix B lookup updates.
Pre-FDP rest
Pre-FDP rest is not a rolling window; it's a per-FDP comparison. The most recent FDP card shows actual rest preceding it versus the §117.X minimum. Tap to see the rest period that fed it.
What feeds the windows
Only Airline Mode FDPs and rest periods feed the rolling-window calculations. Pre-Airline-Mode flights (logged before you toggled Airline Mode on) are ignored by the §117 math.
If you backfilled the previous 14 days of FDPs and rest when you enabled Airline Mode, the windows have full context from day one. If you skipped the backfill, expect the cards to show "insufficient history" until 14 days of in-mode data accumulates.
What doesn't feed them
- Manual flight entries without an associated FDP. The flight contributes to your career flight totals but not to §117 cumulative counts.
- Cancelled trips logged with zero block time. If the FDP started, the report-to-release duration counts toward FDP cumulative even if the flight didn't occur. If the FDP didn't start (you were canceled at home before report), don't log it.
- Personal flying. If you fly your own SR22 on a day off, that's not Part 121 duty and doesn't feed §117 counts.
Tips from pilots
Glance at the dashboard once a week, not after every flight. The pressure trends are what matter, not the exact value after each leg. Sundays before a trip is a good cadence.
If the §117.23(c)(1) (60-hour weekly FDP) card is consistently amber or red on Mondays, your operator is scheduling you with thin margins. That's not a DaPilot problem; that's a roster trade conversation.
When you submit a trip trade, run the trade through the windows: if the pickup pushes any window past 90%, ask your scheduler to confirm before you accept. The scheduler has the official math; DaPilot lets you sanity-check it.
· 10 min read