How to Convert Kilometers per Hour to Mach Number
When analyzing aircraft performance, there is often a need to convert from standard speed units like kilometers per hour (KPH) to Mach number. While KPH provides absolute airspeed, Mach represents velocity relative to the local speed of sound. This guide outlines the basic KPH to Mach conversion process.
Reviewing Mach Basics
As background, the Mach number is defined as:
Mach Number = Aircraft Velocity / Local Speed of Sound
Since the speed of sound varies by altitude and other factors, reference tables are used to determine the appropriate conversion value:
| Condition | Speed of Sound |
|---|---|
| Sea Level | 1234 KPH |
| 10,000 m altitude | 1112 KPH |
| 20,000 m altitude | 1051 KPH |
So Mach 1 is 1234 KPH at sea level per the standard value.
Calculating Mach from KPH
To transition from KPH to Mach number, you simply divide the aircraft’s KPH by the reference speed of sound for the flight conditions.
For example, an aircraft traveling 885 KPH at 20,000 m altitude is moving at a Mach number of:
885 KPH / 1051 KPH = 0.84 Mach
This gives speed as a ratio of the reference speed.
Key Takeaways
In summary, to go from KPH to Mach number:
- Mach number is aircraft velocity/speed of sound
- The speed of sound varies by conditions like altitude
- Reference tables provide the speed of sound values
- Use KPH/reference speed of sound = Mach number
- Use Mach * reference speed of sound = KPH
So with the proper speed of sound reference, standard metric airspeeds can quickly convert to Mach number ratios.
Type a value in the KPH field to convert the value to Mach:
Mach:
KPH to Mach Formula
Mach=KPH/1225.044
Other Value
1710 kph to mach
1.39
51308 kph to mach
41.88
1000 kph to mach
0.81
8000 kph to mach
6.53
convert 2070 kph to mach
1.68
32000 kph to mach
26.12
17000 kph to mach
13.87
18000 kph to mach
14.69
1098 kph to mach number
0.89
26722 kph to mach
21.81
KPH to Mach Conversion Chart
| KPH | Mach |
| 1 | 0.000816297 |
| 5 | 0.004081486 |
| 10 | 0.008162972 |
| 20 | 0.016325944 |
| 30 | 0.024488916 |
| 40 | 0.032651888 |
| 50 | 0.040814861 |
| 60 | 0.048977833 |
| 70 | 0.057140805 |
| 80 | 0.065303777 |
| 90 | 0.073466749 |
| 100 | 0.081629721 |
Related Converters
1. MPH to KPH
2. MPH to Knots
3. MPH to Mach
4. KPH to MPH
5. KPH to Knots
6. KPH to Mach
7. Knots to MPH
8. Knots to KPH
9. Knots to Mach
10. Mach to MPH
11. Mach to KPH
12. Mach to Knots