MQ4135
MQ4135 (Envoy Air) is a multi-stop service on 12 routes, busiest St Louis to Chicago. Of 436 departures recorded from December 2024 to July 2026, 86.4% left on time, according to the US BTS.
- On-time departures86.4%of 436 flights
- Average delay11.4 min
- July 202662
- Cancelled0.2%
- Legs flown under this number12
Recorded departures by month
All legs under this number combined; see the leg table.
Months without data are left blank.
The most recent periods15 periods
| Period | Departures 2025 | Departures 2026 | Change vs last year |
|---|---|---|---|
| January | 14 | – | – |
| February | 4 | 4 | 0.0% |
| March | – | 10 | – |
| April | 34 | 24 | ▼ 29.4% |
| May | 56 | 41 | ▼ 26.8% |
| June | 8 | 60 | ▲ 650.0% |
| July | – | 62 | – |
| August | 14 | – | – |
| September | 58 | – | – |
| October | 35 | – | in progress |
| November | 1 | – | – |
| December | – | – | – |
according to the US BTS · December 2024 → July 2026
On-time departures by month
Months without data are left blank.
On time = departure within 15 minutes of schedule. Non-cancelled flights with a recorded delay only.
The most recent periods15 periods
| Period | On time 2025 | On time 2026 | Change vs last year |
|---|---|---|---|
| January | 85.7% | – | – |
| February | 100.0% | 100.0% | 0.0% |
| March | – | 80.0% | – |
| April | 94.1% | 87.5% | ▼ 7.0% |
| May | 87.5% | 78.1% | ▼ 10.8% |
| June | 50.0% | 83.1% | ▲ 66.1% |
| July | – | 87.1% | – |
| August | 71.4% | – | – |
| September | 94.8% | – | – |
| October | 91.4% | – | in progress |
| November | 100.0% | – | – |
| December | – | – | – |
according to the US BTS · December 2024 → July 2026
Average departure delay by month
Months without data are left blank.
according to the US BTS · December 2024 → July 2026
Cancelled departures by month
Months without data are left blank.
The most recent periods15 periods
| Period | Cancelled 2025 | Cancelled 2026 | Change vs last year |
|---|---|---|---|
| January | 0 | – | – |
| February | 0 | 0 | – |
| March | – | 0 | – |
| April | 0 | 0 | – |
| May | 0 | 0 | – |
| June | 0 | 1 | – |
| July | – | 0 | – |
| August | 0 | – | – |
| September | 0 | – | – |
| October | 0 | – | in progress |
| November | 0 | – | – |
| December | – | – | – |
according to the US BTS · December 2024 → July 2026
This is a historical record of departures already flown, not a forecast for your flight.
Several legs: the headline figure averages all of them. See the leg table.
Cancellation share
- Not cancelled 99.8% 435
- Cancelled 0.2% 1
Share of all recorded flights in the period, all legs. · Dec 19, 2024 → Jul 31, 2026
On time, leg by leg
Departures within 15 minutes of schedule; small figure = departures recorded.
Legs flown under this number
6| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| STL ORD St. Louis Lambert International Airport – Chicago O'Hare International Airport | 415 | 24.3 min | 84.3% | 108 |
| TUL ORD Tulsa International Airport – Chicago O'Hare International Airport | 941 | 17.5 min | 77.5% | 72 |
| ORD TUL Chicago O'Hare International Airport – Tulsa International Airport | 941 | 2.1 min | 91.7% | 72 |
| ORD STL Chicago O'Hare International Airport – St. Louis Lambert International Airport | 415 | 6.4 min | 86.7% | 45 |
| RAP CLT Rapid City Regional Airport – Charlotte Douglas International Airport | 2,124 | -1.2 min | 93.9% | 33 |
| CLT RAP Charlotte Douglas International Airport – Rapid City Regional Airport | 2,124 | 5.2 min | 97.0% | 33 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| December 2024 | 11 | 11 | 81.8% | 0 |
| January 2025 | 14 | 14 | 85.7% | 0 |
| February 2025 | 4 | 4 | 100.0% | 0 |
| April 2025 | 34 | 34 | 94.1% | 0 |
| May 2025 | 56 | 56 | 87.5% | 0 |
| June 2025 | 8 | 8 | 50.0% | 0 |
| August 2025 | 14 | 14 | 71.4% | 0 |
| September 2025 | 58 | 58 | 94.8% | 0 |
| October 2025 | 35 | 35 | 91.4% | 0 |
| November 2025 | 1 | 1 | 100.0% | 0 |
| February 2026 | 4 | 4 | 100.0% | 0 |
| March 2026 | 10 | 10 | 80.0% | 0 |
| April 2026 | 24 | 24 | 87.5% | 0 |
| May 2026 | 41 | 41 | 78.1% | 0 |
| June 2026 | 60 | 59 | 83.1% | 1 |
| July 2026 | 62 | 62 | 87.1% | 0 |