(For Sample Questions Only)
TABLE 2 - SAE TYPE II FLUID HOLDOVER GUIDELINES FOR WINTER 2003-20041
THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER
OAT | Type II Fluid Concentration | Approximate Holdover Times Under Various Weather Conditions (hours:minutes) | |||||||
°C | °F | Neat Fluid/Water (Vol%/Vol%) |
Frost2 | Freezing Fog | Snow | Freezing Drizzle4 | Light Freezing Rain | Rain on Cold Soaked Wing | Other5 |
100/0 | 12:00 | 0:35 - 1:30 | 0:20 - 0:55 | 0:30 - 0:55 | 0:15 - 0:30 | 0:05 - 0:40 | |||
above 0 | above 32 | 75/25 | 6:00 | 0:25 - 1:00 | 0:15 - 0:40 | 0:20 - 0:45 | 0:10 - 0:25 | 0:05 - 0:25 | |
50/50 | 4:00 | 0:15 - 0:30 | 0:05 - 0:15 | 0:05 - 0:15 | 0:05 - 0:10 | ||||
100/0 | 8:00 | 0:35 - 1:30 | 0:20 - 0:45 | 0:30 - 0:55 | 0:15 - 0:30 | CAUTION: | |||
0 to -3 | 32 to 27 | 75/25 | 5:00 | 0:25 - 1:00 | 0:15 - 0:30 | 0:20 - 0:45 | 0:10 - 0:25 | No holdover | |
50/50 | 3:00 | 0:15 - 0:30 | 0:05 - 0:15 | 0:05 - 0:15 | 0:05 - 0:10 | time | |||
below -3 to -14 |
below 27 to 7 | 100/0 | 8:00 | 0:20 - 1:05 | 0:15 - 0:35 | 0:15 - 0:453 | 0:10 - 0:253 | guidelines | |
75/25 | 5:00 | 0:20 - 0:55 | 0:15 - 0:25 | 0:15 - 0:303 | 0:10 - 0:203 | exist | |||
below -14 to -25 |
below 7 to -13 | 100/0 | 8:00 | 0:15 - 0:20 | 0:15 - 0:30 | ||||
below -25 |
below -13 |
100/0 | Type II fluid may be used below -25°C (-13°F) provided the freezing point of the fluid is at least 7°C (13°F) below the OAT and the aerodynamic acceptance criteria are met. | ||||||
Consider use of Type I when Type II fluid cannot be used. |
°C = Degrees Celsius | °F = Degrees Fahrenheit | OAT = Outside Air Temperature | Vol = Volume |
NOTES
1 | Based on tests of neat fluids with the lowest viscosity deliverable on the aircraft, yet meeting Type II WSET and HHET. |
2 | During conditions that apply to aircraft protection for ACTIVE FROST. |
3 | The lowest use temperature is limited to -10°C (14°F). |
4 | Use light freezing rain holdover times if positive identification of freezing drizzle is not possible. |
5 | Heavy snow, snow pellets, ice pellets, moderate and heavy freezing rain, and hail. |
6 | |
7 | Ensure that the lowest operational use temperature (LOUT) is respected. |
CAUTIONS
- The time of protection will be shortened in heavy weather conditions, heavy precipitation rates, or high moisture content. High wind velocity or jet blast may reduce holdover time below the lowest time stated in the range. Holdover time may also be reduced when aircraft skin temperature is lower than OAT.
- The only acceptable decision criteria time is the shortest time within the applicable holdover time table cell.
- Fluids used during ground deicing do not provide ice protection during flight.