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Aviation Safety

AVIATION SAFETY

Dave Fry, WVFC CFI and Aviation Safety Counselor dgfry@aol.com

 

Talk to Me, Goose!

 

That may not be everyone’s favorite line from “Top Gun”, but we all remember it.  It has a different meaning in this article, but it definitely is appropriate. All airplanes speak to their pilots, and good pilots listen, but you have to understand the language.

 

I just spent a week in Alaska working on Commercial Multi-Engine Sea flying a military configuration Grumman Goose, and without a doubt it speaks a language different from anything in the land-based club where I do much of my flying.   Peripherally, you used to be able to add the rating on at the ATP level, but now you need 50 hours PIC in Category and Class to qualify for the check ride – I have no idea if that’s EVER going to happen, or what bizarre (if welcome) concatenation of events would lead to it.

 


GRUMMAN N703

 

First of all, everything on the plane is over-engineered and overstressed and built.  If it’s both-engines-out glide ratio is reminiscent of what you get with a Diebold safe or some of your finer pianos, there’s a reason – it’s built like a tank.  An additional feature of this construction/weight is that in most airplanes if you find yourself a bit slow on final, you simply lower the nose a couple of degrees and if needed, add a bit of power to keep the descent path on the VASI.  In the Goose, you lower the nose, and pretty much nothing happens to the airspeed unless the new pitch attitude is ten or more degrees nose down from the previous pitch, in which case you MAY get the speed you need, but you’ll need to be patient and you’ll need to add a LOT of power to keep the same descent path.  The good and bad news simultaneously is that it’s a RARE waterway with a VASI or PAPI.

 

Second, there are LOTS of systems that are somewhere between “different” and “bizarre”.  “Quaint” doesn’t quite cover it.  For example, when’s the last time you saw a plane with split flaps?  OK, we’ve seen them on a Twinstar, but powered by vacuum from the carburetor?  It also has the normal radial engine quirks, such as hitting the starter and counting nine prop blades before turning the magneto on, and an oil capacity measured in gallons rather than quarts (five to six is normal, with four as a minimum).  This results in much longer than normal engine warm-up times, as the lower limit for RPM above 1000 is 40 degrees C. There is also a CHT limitation that is a minimum of 100 C for takeoff, but it’s reached WAY before the Oil temp gets up to 40.  By the way, checking the oil quantity is a combined exercise in gymnastics and mountain climbing.  You start by climbing the ladder toward the door, stand on the doorstep and climb up onto the trailing edge of the wing.  Then you walk up to the top of the wing and engine of your choice.  My preferred technique at this point is to straddle the engine nacelle and unscrew the oil dipstick.  It’s a LONG way down from up there, and I have a thing about heights.  Getting back down is even worse, since you can’t see where your foot is going and you have to feel for it while you’re far enough above the ground that you really wouldn’t want to fall.

 

It has a simple fuel system, and while it is unusual, it actually makes sense.  The fuel gages are clear vertical tubes filled with the fuel from the tanks (each with a small orange bead floating atop the fuel so it’s easy to see the top of the fuel column) that are calibrated on two scales: one for level on the water or cruise flight, and one for the taildragger position on land. The fuel selector valve has three positions, BOTH, LEFT, and RIGHT, and unlike most twins, there’s only one fuel selector, not one per engine.  

 

 

 

 

FUEL SELECTOR VALVE

 

Both engines run off whatever is selected.  If “BOTH” is selected, the engines run off both tanks; if “RIGHT” is selected, both run off the right tank, similarly for the “LEFT” selection.  The Murphy’s Law Corollary to this is that if you select one tank and run it dry, BOTH engines quit.  See the glide ratio conversation above.  

 

The “Fuel Cross Feed” valve doesn’t actually cause fuel to flow from one tank to the other (there is no way to do that); it allows the engine-driven fuel pump on one engine to provide pressure to the other engine – a great way to prime the second engine.  

 

But before that (for starting the first engine), since there isn’t an electric backup fuel pump, you get to supply the fuel pressure by using a thing called a “wobble pump”, which you use with your right hand just over and behind your right shoulder.  Of course, it’s not actually that simple; before pumping, you have to select the engine to be primed, then while pumping you need to hold the primer switch on the overhead panel.


 

WOBBLE PUMP

 

There’s little that’s electrical on the plane. If you have a total electrical failure, you lose radios, navigation, lights, the turn and bank indicator, and the pitot heat.  Nothing else on the plane is electrical.

 

Unlike most airplanes with retractable gear there is no back-up gear extension system, since the primary system is manual.  I suppose you could consider the second pilot (if you have one) to be the back-up.  There’s a lever (called a gear pawl) that determines which direction the gear will go when you crank.  


 

GEAR CRANK AND GEAR PAWL

 

And, by the way, it takes about 40 turns of the crank whether raising or lowering the gear.  Some of the turns are so easy you aren’t even sure anything is happening, and some are so hard you want to get both arms in there.   Even more fun, this is done mostly while in the water. You taxi down a ramp into the water, and when you begin floating (steering with your left hand using differential throttles – there are no water rudders), you start cranking.  The first couple of times this results in some serious course deviations.  Same thing in reverse when returning to the ramp.

 

The power controls aren’t where you’re used to them being: The throttles, props, and mixture are on the overhead panel, as are the Flap controls, CHT, Oil Temp, Oil Pressure, Fuel Pressure, Carb Air Temp, and Outside Air Temp gages.  The Magnetos are up there, too.  And the configuration is a bit different, as well.  Instead of both throttles on the left of the power quadrant, both prop controls in the middle, and the mixture controls on the right, the mixture controls are on either side of the throttles and the prop controls are aft and above the throttles.  Carb Heat is even farther to the right.


 

OVERHEAD PANEL

 

The battery and alternator switches are on the side of the door into the cockpit – conveniently with a guard over them to keep you from breaking them off on your belt loop as you enter the cockpit. The Fuel Selector Control is directly behind the pilot’s head, and the Cross-Feed control is directly above the door into the cockpit.  The elevator trim control is on the right side of the pilot’s seat (which is not adjustable in any direction), and the rudder trim control is on the sidewall left of the pilot, as is the tailwheel lock.

 

For those of you that have flown floatplanes, the plugs on the hull are nothing like the squash ball jammed into the float that you may be used to.  They’re half inch screws removed from the lower part of each hull chamber by a ¼ inch Allen wrench. 


 

PLUGS

 

Plan on lying on your back or side removing and replacing them every day.  And there are a lot of them – 5 on the left side forward of the main step, 4 on the left side between the main and the secondary step, and three more aft of the secondary step.  There are also three back up plugs on the right mid side, as well as three on each of the wing floats.

 

The plane doesn’t have tailwheel steering; so, steering is done by a combination of differential braking, differential power, and rudder input.   When you’re in the water, of course, brakes simply don’t work.  You can press them, and the wheels don’t turn, but it’s an exercise in futility; the plane is going to keep moving as if you hadn’t touched the brakes.  I know. The word “klutz” comes to mind along with the occasional cramped calf muscle – lack of success didn’t keep me from trying.  Even on the land part of the taxi, the tailwheel seems to have a mind of its own. Just like the one on a Citabria, it can “break away” and move independently of any other input.  So, you brake a little, get nothing, brake more, still nothing, add some more brake, and now the whole aft end is swinging sideways with no control until you hit the opposite brake hard enough to make it stop swinging.  Leading the desired heading is critical.  And it works far better the second day of training than it does the first day.  I spent most of the ground taxi time moving slower than your doctor does when backing the Mercedes out of the garage. The most fun part of this (instructors think it’s fun, anyway) is that if you start the engines in the water, when the first engine is going, you begin turning, and there’s NOTHING you can do about it until you get the other one going.  The second time you do it, you prime both engines before starting the first one.

 

Takeoff is begun with the wheel all the way aft, and full right aileron (which is about 50 times what you use in the average turn entry – about 90 degrees of turn on the wheel.  With 900 HP between the two radials, there is a LOT of torque and P-factor wanting to make the plane roll to the left, so you kinda lock your forearm around the wheel and put your back into it to keep the wheel aft.  Even when trimmed, this is a VERY physical airplane. Ten minutes into the flight, I was sweating like a pig in a steam bath!  And I like to think of myself in some kind of shape (whatever the level of truth of that thought).

 

Bring the power up to 30 inches of manifold pressure to begin the takeoff.  As the speed comes up, so does the nose, and when it reaches its highest point, you lower it, take the flaps from zero to 30 degrees, and increase the power to max – around 35 inches.  Somewhere in the process, you get the wings level, all the while holding your heading and keeping the pitch at an attitude that will minimize the drag from the water. This is non-trivial.  A few degrees nose down from that attitude and you begin to porpoise.   A few degrees too high, you begin to porpoise.  But there is a sweet spot; you just have to fish around to find it – unless you’re the instructor, in which case the sweet spot is intuitively obvious, and you wonder why people have so much trouble finding it.

 

A few moments later you’re airborne, and the object, much like a ground-based soft field takeoff, is to accelerate in that attitude without really trying to gain altitude.  This is done while raising the flaps and reducing the power to 30 inches and 2000 RPM, and then you pitch up to climb out at 90 Knots. There are a couple of technique choices here regarding control forces.  You can leave the trim where it was for takeoff, in which case you get a full body workout and can forgo the trip to the gym after the flight, or you can use the trim, which means you are going to be doing that a lot.  In our club planes, I teach that anytime you change the airspeed, power, or flaps, trim to keep the plane doing what you want it to do.  This airplane is the reason for those rules (I didn’t know it at the time I adopted that rule, but sometimes I DO get it right.)

 

Some of the maneuvers required for the Commercial MES are the same as those required for a Commercial MEL or Commercial SEL, for that matter – steep turns, slow flight, stall recoveries.  On the other hand, you substitute glassy water landings for soft field landings, accuracy landings for short field landings – single engine approach and landings remain the same.  Then there is ramping and docking, step taxi, and “sailing”, which involves using the aerodynamics of the plane to move sideways while being blown backward by the wind.  This maneuver is 20 percent science, and 80 percent art.

 

At the end of my training, I had 10 hours of flight training in the Goose, but like most airplanes, especially complex ones, it will take MANY more before I even BEGIN to master it.  On the other hand, if you ever get the chance to end up in Anchorage for a few days – even if you don’t want to get an MES rating, visit the Goose Hangar (https://www.goosehangar.com) and fly with Burke Mees.  He’s an insightful, totally professional instructor that will give you far more than your money’s worth.



 

And you get to fly a classic piece of aviation history that will talk to you in a language you’ll begin to appreciate.

 

I have hopes I can have the Goose talk to me again next year.

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