Sometimes watching the Original Forum on JustHelicopters can pay off. For most of the last 1.5 weeks, “Capt Easy” has been throwing out training scenarios and letting everybody bicker over them. Just sorting out the trash talk though, can be difficult enough, but on top of that, scenario based training (SBT) also requires a little bit of extra effort to arrive at the take-home lesson. In this scenario, Capt Easy was looking for problem solving skills when faced with inadvertent instrument meteorological conditions (IIMC) at night. It looks like a pretty nasty situation to begin with, and not something a low time pilot should be faced with for many years (most of the scenarios have been targeted at HEMS pilots it seems). This scenario does get at one thing that is introduced into every pilot’s early training though, and you’ll see it come up in the discussion. Also, the scenario assumed the aircraft was equipped with at least basic instruments (ie, not your stock R22) or was IFR-capable. Okay, here’s the situation (slightly edited):
It’s winter and there’s snow on the ground. It’s also night time, and there’s an overcast layer that’s not real high, but it’s high enough that you can easily fly below it. The visibility is >5 sm. The METAR and TAF both say you can easily make the 30-minute flight back to your base under VFR.
You depart with full fuel for home. About halfway through the flight, you find yourself flying through a snow shower with good (but still reduced) visibility. Suddenly everything goes black–no lights in front of you our below you on the ground. You just went IIMC. What’s your plan?
The first step, which will be a post for another day, is figuring out what just happened. Sitting here reading words on a screen, it’s not so difficult, but imagine it happening real-time. There’s actually a mental process that you go through when the unexpected happens, and getting through that is the first step to making the proper response. But that’s not at issue here. What matters is that you are now in IMC.
The “discussion” broke into 2 camps: do a 180 degree turn back to VMC, or climb and contact ATC.
The 180-degree turn back to VMC
The rationale here is that you know what the weather is behind you, so why not just go right back to it? I can’t say where I heard this first, but I’ve heard it many times: the lifesaving 180 degree turn. Detractors to this response have a good point though: many good pilots–even instrument-rated pilots–kill themselves trying to make that 180 degree turn out of an IIMC encounter. And it is true that turning puts you at risk for spatial disorientation and all those sensory illusions that you read about in the PHAK. Conclusion:never make a 180 degree turn, especially at night.
Climb, contact ATC, get vectors to VFR or an ILS
Okay, turning is dangerous, so climb out. Can’t hit the ground if you’re high enough above it, right? Additionally, you can then contact ATC and get their help. This is advice has also been doled out, especially with respect to lost procedures, and you might remember it as the 3 or 4 C’s (Climb, Confess, Communicate, Comply, Conserve, etc, etc). The other side of the argument goes that climbing will guarantee that you remain in IMC, increases your workload (especially if you aren’t proficient), and might stick you in icing conditions. Conclusion: climbing is for morons.
Other options then?
There is actually a “right” answer in there. Both sides make good points for and against their approaches to the problem. So how do you approach this scenario? It starts during your pre-flight planning, and from there adapts to your circumstance.
- Plan an en route altitude for obstacle clearance. In my training, we usually flew as low as possible (500-800 AGL). Lots of reasons for that, but in this case it’s night with surrounding weather. You want to be high enough that if you suddenly can’t see obstacles around you, you know that you can safely make turns or continue straight ahead without hitting them. The easy way to do this is to fly above the Maximum Elevation Figure (MEF) on your route. Not always practical, especially if you fly adjacent to high terrain. What I’ve done for my night VFR flights is planned them as if they were IFR, climbing to some altitude above the highest obstacle within 4 NM of my flight path. Once you have your instrument rating, your ways of thinking about how to establish an en route altitude open up: MEAs, OROCAs, the 4 NM rule, MSAs….
- In flight, set a hard deck that will maintain obstacle clearance. At the RHC Safety Course, somebody recommended turning around or landing if you have to descend twice because of weather. I think this advice is mostly a way of imposing a limit on how many times you’ll descend to stay clear of the ceiling, and not necessarily something you should follow. But if you do, plan your en route altitude to take this into account. If you’ve made a descent and are now below your highest obstacle, your options have changed.
- In an IIMC encounter, you don’t have to react fast. IIMC might be an emergency, but your response shouldn’t make a bad situation worse. To me, this one bit of advice settled the whole argument. Fly the aircraft. Get level and in trim. Relax. Commit to flying by the instruments. Once you’re in a stable situation, decide what you’re going to do. Turning when you haven’t fully transitioned to instruments does put you at risk for spatial disorientation, and climbing might not be necessary. This article from AOPA summarizes the rationale nicely.
- Once you are flying straight and level by instruments, decide whether a climb or turn is indicated. Climb if you’re below your highest obstacle. If not, consider a turn if you still think there’s VMC behind you. Or contact ATC and utilize that resource. Either way, with the aircraft under control and your mental state adapted to the situation, you have time to think.
- Stay on your instruments. Transitioning back to VFR from IFR can be a challenge, and for most of us, the closest we’ve come is flipping the hood out of the way. Getting partial spatial information from your peripheral vision or as you’re coming in and out of IMC is another risky area.
This could start as a lesson in determining en route altitudes for a night flight. Set your student up to do a night flight, and ask him what altitude is appropriate (although for a lesson in an R22, the decision would probably be to not make the flight, so you have to tweak that). Once he’s IIMC, you can discuss the decision-making processes that his flight planning left him with. The last part is discussing alternative options that he might not have considered. In this case, Capt Easy set up his flight so he was high enough that obstacle clearance wasn’t a concern. He transitioned to instruments, and made a 180-degree turn back to VMC. If he’d been in an R44, not instrument-proficient, and had descended to below his highest obstacle, his decision-making process would have been different.
The key lessons here are:
- Your en route altitude should take into consideration the conditions you expect to encounter during the flight;
- Changes to your altitude en route will also affect the options available to you if you encounter IIMC;
- If you are IIMC, aviate first: control the aircraft and commit to flying by instruments;
- Once the aircraft is under control, you have time to determine the best course of action.