Last Week in the Forums: Check ride and alternator failures

A thread on VR this week about the alternator light is another example of why I’m doing this. In the R22 POH, the alternator light emergency procedure gets just a paragraph and is pretty straightforward: alternator switch off, non-essential equipment off, alternator switch on. Land as soon as practical if the light remains illuminated.

The thread on the forums this week started with a cracked drive belt, but moved into a discussion about the mechanical reasons the alternator light might become illuminated the grief that could cause you. In the POH, the primary concern is loss of electrical power, which would cause a failure of the governor and tachometer, and no way of regulating your MR RPMs. Even without an alternator, the battery should have 10-15 minutes of reserve power, allowing you to follow the procedure for landing as soon as practical (go to the nearest airport where repairs can be made). What isn’t in the POH is the risk of a loose alternator belt flying around the engine compartment. Once freed from the pulleys, it can become entangled in the drive belts, leading to their failure and an emergency autorotation. This is exactly what happened in a September 2007 accident. In this case, the first indication of a problem was the sound of the alternator belt breaking, followed by RPM instability. However, one of the posts on the VR thread suggested a scenario where an alternator light could indicate a failing alternator or alternator bearing, leading to failure of the belt itself. Even if the drive belts aren’t damaged, the belt that came loose in the 2007 accident contacted the oil cooler and lines. Conclusion? Consider making an emergency landing if the alternator light illuminates, and figure the problem out on the ground rather than in the air.

The other thread that was really interesting was about a pilot who failed his commercial ride. Basically, his instructor filled the tanks on the helicopter while the pilot was doing his ground portion of the check ride. He didn’t recalculate the W&B for the actual fuel load, and ended up 16 lbs over MGW. Shitty way to learn a lesson, but props to this guy for posting is story. I wonder if there’s an inherent complacency toward fuel because we do it so casually for our cars (except in Oregon and New Jersey!). Planning your fuel load is the first important step, but what got the pilot on his check ride was confirming what went in. Where I trained, we did the fueling ourselves, but I’ve been to plenty of airports where you touch down to refuel, and a truck comes bounding over to you. These guys aren’t going to attach the same importance you are of putting on exactly what you tell them. This job would be easier if you could always trust your fuel gauges or had a dipstick for exactly determining your fuel load. If you have the R22 weight and balance calculator and a smart phone with an Excel application (like Grid Magic), you can recalculate your fuel load right after you finish fueling.

A bigger problem that I’ve seen is not testing fuel for water or debris. Flying out of the same airport, you get to trusting your fuel source. Out in the real world–where you’re going to be flying from different locations, maybe getting fuel from barrels cached in the woods of North BFE–having a well entrained habit of always checking your sump might be a good idea. Since I learned to fly airplanes at an airport with a fuel service, I got into that habit. But another good reason is that things change, and you don’t always realize the implications. While working on my instrument rating, I started seeing rust particles popping up in the sump. This was after months of not having any indication of a problem. Turns out, the pump on the fuel truck was switched out while the original was being serviced, and that was the source.

Here’s another good one. Before you pulled the helicopter out of the hanger this morning, you checked the sumps and it looked good. It’s 10 degrees C outside and snowed last night, so you’re happy this will be a quick refuel–just 3 gallons. You drive the fuel truck from the tank out to the ramp, pick up the nozzle, pop it in the tank, and get your fuel. You know the truck is topped off every night, and you’ve never had debris or water come out of this tank. So, is there a good reason to check the sumps again? Anybody make a guess. Bueller? Bueller?

On an unrelated note, a couple of weeks ago, N74607, my favorite of all the R22 Beta IIs that I’ve flown, met it’s end in the Owyhee mountains. No injuries, and maybe it’ll fly again.

Conducting a Flight Review

As a new CFI, a flight review is something you could get called on to do out of nowhere. This is a challenge for the new CFI who’s not working at a flight school: you’ve never been through a flight review yourself, you have nobody to ask for advice, and you are very likely giving the review to somebody with hundreds of more hours experience than you. The instructors I’ve talked to have learned a lot when doing flight reviews, but it doesn’t mean that you don’t bring anything to the table. You actually have an advantage–your book knowledge is current, and that’s one of the most important parts of the flight review. As a new addition to the resources area, I put together a guide for helicopter CFIs conducting a flight review, and assembled a few resources for you to use. Check it out here.

Part 61 Changes

Wouldn’t you know it, I just found out about several changes to the FARs that might affect the endorsements, and will definitely affect the requirements for the PPLH and CPLH certificates. That’s supposed to be part of the power of a wiki though–that user communities keep the content evergreen. The rules go into effect late in October, and are summarized here [FAR Changes] and in an AOPA article. The duration of student pilot certificate pilot certificates is now the same as a 3rd-class medical. There’s also a change in the definition of cross-country time, although it’s hard to tell from the AOPA write-up how it applies to helicopters. Looks like I’ll have to dig into the regs some to figure that out.

One thing that didn’t change was the requirement for maintaining instrument currency. The FAA had proposed adding a cross-country flight and specific procedures and approaches.

Quick Weight and Balance Calculator Beta Release

Don’t want to read about it? Download the calculator now!

Note: These instructions refer to an older version of this calculator. You can still download it from the above link, and view version 3’s features on the Weight and Balance Calculator B3 release page.

Do you run a weight and balance before every flight? Or do you just guesstimate how much fuel you can carry and assume you’ll be close enough to being in CG? I know guys who don’t do a W&B except for check rides. Not good enough for me. Limitations are limitations, and early in my training I developed worksheets for each helicopter so that I had the baseline CG values for every flight. From there it was easy to add a weather check, and HIGE/HOGE calculations into my pre-flight routine.

Now, there are plenty of these already out there. Maybe your flight school has one. I put some real thought into this though to make it user-friendly and packed with features. First, on the Conditions page, you fill in the red boxes with the basic empty weight and arm data. Password protect the worksheet and nobody can inadvertently alter those values. Next, enter all the variable data into the green boxes: pilot and passenger weight, baggage weight, optional equipment (default is installed), and fuel. After the passengers and baggage weights are entered, the Calculator displays the maximum allowable fuel weight (which may be greater than the fuel capacity). The CG graph is updated automatically with the take-off (solid green) and zero-fuel (open white) conditions. Endurance is based on a an editable burn rate (usually 8-10 gph). This is a quick and clean way for students to see how CoG shifts and changes during flight. By unlocking the red cells, they can develop a better understanding of how weight and arm are related to payload capacity.

Quick Weight and Balance Beta Screen shot

I thought about hiding the calculations page altogether, but as a learning tool it’s great. Your students can complete calculations by hand and then check their calculations there. For a beta version, this is also a good troubleshooting tool.

The student worksheet is meant to be used day-to-day for manual calculations. The graphs, arms, weights, capacities, and limitations are reproduced from my POH, but you must confirm that they are consistent with your aircraft’s POH. All cells are unlocked and the sheet is unprotected so you can enter the data for your aircraft. The rest of it is simply an intuitive template for doing W&B calculations and gathering pre-flight data. It should also print out very nicely.

A few disclaimers. I have tried it with several helicopters and it works fine. They are all Beta IIs though. I also run Windows Vista and Microsoft Office 2007, so I have no idea how the Calculator will work with your system. I do know–and this one’s important kiddies–that you must enable active content and macros. The ultra-histrionic Office 2007 automatically disables these features unless you tell it to enable them. I also locked the worksheet so that you’d have to read the instructions. Getting the unlock is easy, but it does require an active internet connection.

I’d like to see some ideas for practice problems that force students to develop a working knowledge of CG. The calculations themselves are only tedious, but applying them to real-world scenarios is what I’d like to get at. In the screen shot, for example, I have to take 240-lb Bubba on a 1.25-hour flight. Can I do it without him having to leave his boots behind?

Anyway, you can download the Quick Weight and Balance Calculator Beta right here or from the Extras! page. This post, however, is where comments, criticsims, corrections, and suggestions belong.