Validation of Preflight Planning 

While discussion in the previous posts focused on the importance of preflight planning, the end goal is execution. Therefore, pilots must validate power requirements and manage power well in the air. A pre-mission power plan has two significant caveats: 

1. Even though predicted power available and power required calculations are critical, if power margins are narrow, pilots cannot assume that predicted equals actual. Pilots should check power available in the aircraft at the pressure altitude and in the configuration for the high power demand. Then, arrive on scene, and compare demonstrated power available and power required in actual conditions. As pilots evaluate narrow margins, they must leave their crew an out (e.g., an escape down and right) and establish a decision gate to wave off/escape.  

2. Deliberate wind and terrain analysis (WTA) is critical to ensuring that the environmental conditions (wind and terrain) are harnessed to improve power margin and aircraft performance, not hurt it. Pilot technique and skill (e.g., the way we fly the helicopter – rates of closure, rates of descent, approach angle, etc.) determine their ability to minimize and anticipate power requirements, making crews capable of executing a mission with narrow margins. To further pilot proficiency, I highly recommend harnessing The High Altitude Army Training Site (HAATS) app (search and download “HAATS” from the App Store), which provides excellent training materials for developing WTA and power management knowledge, skill and technique.  

With respect to on scene evaluation (comment 1 above) – Cruise charts and Tab data provide exceptional prelaunch situational awareness, and en route, the CDU allows pilots to plan. That said, as pilots approach scene, they must evaluate in real time because validating the power available and having the awareness of whether the helicopter is Ng/fuel flow or TGT limited, is beneficial. 

Power available check: The MH60T flight manual power available check is very specific. It is designed to check power available with engine anti-ice on and contingency power off. The MH60T community should improve the simplicity and utility of power available checks. To do this, pilots need only to be near the on scene altitude and temperature, configure the helicopter’s bleed air (engine anti-ice) and contingency power (I recommend on), then decrease a PCL (if necessary) and increase power until Nr drops. Although at higher altitudes a power available check is more critical, it is also easier to conduct. There is no need to manipulate PCLs, and with maximum torque available less than 106%, there is no torque timer. Ideally, pilots conduct a power available check by getting slow (on the back side of the power required curve). If the helicopter is fast, pilots must account for the ram air effect, which provides 4-5% additional power. Within a couple of minutes, pilots determine actual MTA. Here is a suggested check: 

1. CONTGCY PWR switch – On. 

2. ENG ANTI‐ICE ‐ As required. 

3. PCL‐ Slowly retard engine not being checked, if required, while maintaining 100% Nr. 

4. Without exceeding combined 212% or SE 135% TRQ, 102% Ng, or 903°C TGT, maintain altitude, adjust air speed and slowly increase collective until 2% Nr droop is obtained, collective is at the upper stop, or any limit is reached. 

5. Stabilize and record TRQ to determine power available. 

6. Adjust collective and cyclic to regain 100% Nr, while maintaining the appropriate altitude. 

7. PCLs – Fly, as required. 

Note: The ram air effect on an engine in forward flight produces 2 to 4% more power than the engine will produce in a hover. If the power available check is completed with airspeed for an operation that will be conducted in a hover, to determine available hover power, deduct the increase in power available, due to the ram air effect. *** Thanks to the pilots who contributed to the development and validation of this simple procedure.

Power required  check:  Pilots must perform a thorough wind terrain analysis (WTA), the purpose of which is to make predictions, set yourself up with an “out” or “escape” (e.g., down and right) to be executed at a decision gate before the helicopter is committed, and then validate the power required predictions before pilots put the helicopter in a position from which they do not have a favorable out.  

Due to large power margins experienced at sea level, the Coast Guard H60 community has to deliberately work to improve on power management. At lower altitudes, pilots need to train with artificial torque limitations to have the skill set to perform at altitude. Regardless of altitude and power margins, pilots can practice power management and torque awareness. Simply, account for the conditions, predict power required to conduct a maneuver (e.g., land, establish a hover, or depart from a confined area), execute the task, note the difference in predicted and actual torque used and then seek to understand why there was a difference. With repetition, the prediction will match actual performance. The ability to predict power requirements accurately and consistently is the first step in mountain flying proficiency.  Next, create artificial torque limitations near your predicted values. Establish decision points. At your decision point, continue the maneuver or execute an escape based on execution and aircraft performance.