Flight Reliability
NK 691 · Spirit Airlines
Chicago → Houston (ORD–IAH)
80
Pretty Reliable
WanderNerd Reliability Score
- 89%
- Arrive within 15 minutes
- 10 min early
- Average arrival delay
- 4.3%
- Cancelled
- 17 min early
- Median arrival delay
Based on 47 historical flights. Data through May 2026.
What the data says
6–9 PM has a slight edge.
Departures between 6–9 PM arrived on time 91% of the time, against 87% between 9 PM–12 AM.
Better than the ORD–IAH route average.
NK 691 arrived on time 89% of the time, versus 75% across the ORD–IAH route.
Better than the Spirit Airlines network average.
NK 691 arrived on time 89% of the time, versus 74% across the Spirit Airlines network.
The breakdown
- Mon—(8 flights)
- Tue—(4 flights)
- Wed—(4 flights)
- Thu—(9 flights)
- Fri—(8 flights)
- Sat—(5 flights)
- Sun—(7 flights)
- 12–3 PM—(8 flights)
- 6–9 PM91%(22 flights)
- 9 PM–12 AM87%(15 flights)
- Departures on time
- 84%
- Diverted
- 0%
- Flights flown
- 45
- Months covered
- 2
Same route, other flights
Keep nerding
Based on 47 historical flights, because apparently we checked. Historical flight data: U.S. Bureau of Transportation Statistics, June 2025 – May 2026. Data through May 2026. How we calculate this.