LIFR Departures from the Runway

In a non-runway environment where outside visual references cannot be maintained in a hover or are expected to be lost during the transition to forward flight, the instrument takeoff (ITO), with or without flight director cues, and the automatic departure (both defined in our flight manual) are the only acceptable means to transition to forward flight.  

Because runway lights and markings provide pilots with some visual cues even in ¼ sm visibility, there are two additional options (four total techniques) for LIFR departures from the runway in low IMC: 

1. The standard flight manual ITOs. 

2. An automatic departure. 

3. A running takeoff followed by an ITO. 

4. An acceleration low to the ground followed by an ITO. 

The flight manual states, “An instrument takeoff or automatic departure should be used when outside visual references cannot be maintained in a hover or are expected to be lost during the transition to forward flight. Conditions requiring the use of an instrument takeoff or automatic departure could be the result of reduced visibility, low ceilings, a lack of visual reference, or helicopter induced conditions such as blowing dust, snow or water. An instrument takeoff or automatic departure is recommended for use during all nighttime overwater departures.”   

The steps prescribed are to initiate a smooth application of collective to climb power. Monitor RADALT, BARALT, and VSI for positive climb indications. Passing 50’, set a 5-degree nose down attitude and accelerate to 70-80 KIAS. Once established in a climb, adjust takeoff power, aircraft attitude, and airspeed as necessary.  

Pros and cons of each technique: 

1. Manual ITO – 

• Pros – This is the primary technique over the water. pilots have manual ITO mins and should be proficient. Therefore, familiarity is the biggest pro.  

• Cons – In low IMC pilots lose visual with the runway environment rapidly. Pilots are in the “goo” at a low airspeed and are committed to continuing flight into IMC at a high-power setting and low airspeed (not great options for a power loss or many other malfunctions). 

2. Auto depart – 

• Pros – Similar to the manual ITO, pilots have mins and should be familiar and proficient. Pilots also have the added benefit of the autopilot facilitating the departure until they are 300’ AGL and 70 KIAS. 

• Cons – Similar to the manual ITO, pilots will lose visual with the runway rapidly and the helicopter will be high and slow with a large power demand. Also, at 300’, the RADALT hold will engage, requiring a pilot to work through the autopilot lowering collective to level off while the other pilot disengages the altitude hold. Stating the obvious, trees and terrain can result in fluctuating RADAR altitudes and subsequent power adjustments. 

3. Running/rolling takeoff followed by an ITO – 

• Pros – The running takeoff allows pilots to accelerate on deck (fixed wing style) with visual cues. If something malfunctions or there is an indication of a pending issue, pilots can abort the takeoff. When pilots lift and enter IMC, they are nearing or at bucket airspeed and have as wide a power margin as possible for continued flight in the event, or an engine failure.  

• Cons – Because pilots typically only depart in low IMC (¼ -½ sm visibility) on operational missions, they do not have the opportunity to train this running takeoff into low IMC. The maneuver requires a pilot to lift level, then relatively abruptly, lower the nose while adding power as they enter IMC. The technique I have seen most is to accelerate to a relatively fast ground speed (e.g., 60 KIAS), which results in the stabilator programming down while the helicopter is still on deck and the subsequent nose tuck creates a lot of motion in the pitch axis. I always minimize pitch attitude changes as much as possible when initially establishing an instrument scan in IMC because I have found that this is the most prevalent cause of spatial disorientation in the MH60-T community.  

4. Acceleration low to the runway followed by an ITO – 

• Pros – An acceleration from 10-20’ allows pilots to accelerate while maintaining the runway’s visual cues (lights and markings). Like the running takeoff, if something malfunctions or there is an indication of a pending issue, pilots can abort the takeoff. When pilots climb and enter IMC, they are nearing or at bucket airspeed and have as wide a power margin as possible for continued flight in the event, or an engine failure. Unlike the running takeoff, pilots can smoothly establish and maintain an accelerative pitch attitude. Once accelerated to an appropriate airspeed (near bucket), pilots typically have an excess of power to climb using collective, allowing for a simple transition to an instrument scan with minimal or no change in pitch attitude.  

• Cons – There is a tendency to climb higher than 10-20’, leading to a loss of visual cues and any attempt to regain them delays the necessary transition to an instrument scan, which can be a critical error low to the ground in low IMC. Pilots must transition to the ITO immediately after (ideally before) losing visual cues. Furthermore, because there are no mins, this is something pilots should practice before the proverbial “dark and stormy” night.      

I favor the acceleration low to the ground using the runway lights and markings. Near the start of the climb, all appropriate AFCS functions (autopilot and roll coupler) can be engaged and a climb using collective with minimal to no change in pitch attitude can be harnessed. This technique not only gives pilots an “out” before climbing into IMC, it also minimizes pitch change, which in turn minimizes the chance for spatial disorientation. 

That said, to be successful, this technique must continually be practiced and well briefed. Here is a sea story… Since I have discussed this technique a lot on syllabus events, most of the aviators I have been stationed with are familiar with it. However, my most recent low visibility IFR departure was with a relatively new army direct commission aviator whom I had not yet had the opportunity to talk to about departures from the runway in low IMC. We were doing an early morning IFR departure to affect an offshore MEDEVAC and it was dark, visibility was ¼ sm. We had a clearance, we reviewed the ODP, took the runway, got our hover checks, as the pilot monitoring I provided cues, and about halfway through the power pull, I realized that I had not briefed my preferred low IMC departure from the runway. Because I was not the flying pilot, we executed a manual ITO with the cues. Moral of the story… use good CRM to maintain a shared mental model AND the manual ITO works well too.