Cockpit report: Grumman G-21 Goose amphibious flying boat

PUBLISHED: 15:23 16 July 2020 | UPDATED: 15:51 16 July 2020

Grumman G-21 Goose amphibious flying boat

Grumman G-21 Goose amphibious flying boat

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A memorable experience of flying a highly original Grumman Goose − tricky to taxi and somewhat laborious on the water but a benign and fun-to-fly machine in the air | Words & Photos: Nick Lee

Some time ago, on one of my working trips to Anchorage, I got talking to the guys at the Commemorative Air Force Alaska Wing about the possibly of flying in one of their aircraft. On my visit to their hangar I met one of the pilots who flies for them, Burke Mees, who mentioned that he also flew a Grumman Goose for the owner and was able to conduct instructional flights.

It seemed like too good an opportunity to miss, so I promised myself that, come another trip to Anchorage with good weather, I’d get it organised with Burke to take a flight. The stars aligned with my July roster and plans were made.

I was operating a flight in from Tokyo that landed at 0430 Anchorage time so Burke arranged to pick me up at the hotel at 0845 to go to the hangar at Lake Hood. That timing worked perfectly for me as my body clock was still on UK time, any later in the day and I’d be wanting to sleep.

The weather was perfect, little wind and unusually warm as Anchorage was experiencing a heat wave with temperatures predicted around 30°. The only issue was poor visibility due to a large number of forest fires in the area.

Burke had sent me a good set of notes on the Goose by email, so I was aware of some of the issues that would come with the aircraft, the primary one being the need to adjust my land aircraft pilot ideas about what constitutes a safe landing gear position on approach! Landing an amphibious aircraft on water with the gear down is a risk that needs to be countered on every approach, as a mistake is disastrous.

Floatplanes tend to flip over, which is bad enough, but with the Goose the nose section would bend upwards, causing a hull breach just ahead of the cockpit which would scoop water in and sink the aircraft in a very short space of time.

The potential for error was not helped by the original cockpit design, which followed the land aircraft convention, the indication lights for gear down being green (up was blue). In Alaska many of the amphibians in use have had those green lights replaced with red ones, as the norm is to land on water, but the Goose also has portholes which allow the pilot to see the position of the opposite side gear from his seat, whilst on his own side it is simply a matter of looking out and down from the side cockpit window.

Burke’s policy for mitigating this particular error is to conduct the landing checklist three times, at cues chosen because they come up in every flight: the first one at the time of the first power reduction from cruise power; the second when the flaps are extended on approach; and one final time when the propellers are moved forward into fine pitch. Each time he checks Burke also looks out of the front of the aircraft and mentally relates the gear position to the surface that he sees – up for water, down for a runway.

Grumman G-21 Goose amphibious flying boatGrumman G-21 Goose amphibious flying boat

Another potential issue that I hadn’t considered was that amphibious hulls and floats are not 100% watertight, so need a way of letting out any water that has gathered during operation. To this end, screw-in plugs are fitted along the length of the hull and floats.

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The life of Grumman Goose N703

The Grumman G-21 was conceived by the Grumman Co of New York as an eight seat commuter aircraft for businessmen in the Long Island area. With its first flight in 1937, it became Grumman’s first monoplane, its first twin-engined aircraft and its first aircraft to enter commercial airline service.

During WWII it served various roles with allied armed forces, including the RAF, who used it for air-sea rescue and called it the Goose. The Goose that I flew, N703, had been delivered to the US Marine Corp as BU 37828 in 1944, serving at several naval air stations including Annapolis, Point Magu and Santa Barbara. It was deemed surplus in the 1960s, and subsequently served with the Fish and Wildlife Department in Alaska.

Grumman G-21 Goose amphibious flying boatGrumman G-21 Goose amphibious flying boat

After being sold to a private owner in 1974, it lay dormant on the shore of Lake Spenard for many years - Burke tells me that several of the leading lights in Anchorage aviation remember playing in and around it as children.

Fortunately it was brought back to life in the 1990s by John Pletcher in a two year restoration project. It flew again in 1996 and has been a familiar sight in the Anchorage area ever since, possibly the most original ex military Goose in existence.

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These are removed at the end of the day to allow any accumulation of water to drain away. All well and good until one forgets to put the plugs back in before flight! So Burke collects them in a tin, which he then places inside the entrance door to the aircraft – a simple but effective defence against the error.

At the aircraft my first job was to refit the drain plugs whilst Burke moved the other resident, a Cessna 185 on floats, out of the hangar with a contraption that would not have looked out of place in a Mad Max film. The Goose was soon out in the open too, and ready for the walk around.

Grumman G-21 Goose amphibious flying boatGrumman G-21 Goose amphibious flying boat

We had a particularly good look at the landing gear−especially the brake lines, as these can get caught and damaged during retraction if they are not properly secured.

With its free castoring tailwheel, the Goose is a tricky enough customer on land when the brakes are functioning−without them it’s a runway excursion waiting to happen! Burke says that he would rather have an engine fire on the Goose than a brake failure, which speaks volumes of the peril of a damaged brake line.

Having checked the rest of the aircraft from ground level it was now time to climb up on the wing via the door and a couple of grab handles onto an obvious and effective non-slip walkway. Getting up on the wing is the only way to check the engine oil and to refuel.

Sitting there between the cowlings of the R-985s we topped the tanks off to their capacity of 220 gallons, which gave us four hours flight time with twenty gallons in reserve. The Pratt and Whitney R-985 Wasp junior is a smaller version of P&W’s first radial, the R-1340.

Grumman G-21 Goose amphibious flying boatGrumman G-21 Goose amphibious flying boat

It’s a robust engine and I am familiar with it from my time flying a Winjeel in Australia and from the Broussard at Breighton.

Mind the tank

With our duties atop the wing complete I made my way inside to open the fuel drain valves on Burke’s command so that he could check for the presence of water in the fuel. It was then time to sit in the cockpit and review the systems. Most of the controls for the fuel system are behind the pilots’ seats.

Although each tank feeds through a single tank selector valve, the important thing here is that, whatever selection is made, both engines are being fed. So, for instance, if the selector is on one tank it is possible to starve both engines of fuel with plenty of fuel left in the other−and the Goose has the gliding properties of a brick outhouse!

Grumman G-21 Goose amphibious flying boatGrumman G-21 Goose amphibious flying boat

There are occasionally good reasons to set the selector to a single tank (eg when refuelling), but for flying the logical selection is ‘both’. As for reading the quantity of fuel, each tank feeds a glass sight tube−one on each side of the cockpit−on the bulkhead behind the pilots.

One last item on the bulkhead is a vacuum line for the gyro instruments, provided by engine-driven vacuum pumps. And there is a separate vacuum system, supplied by the carburettor venturis, which drives the flaps.

Having reviewed the fuel system we got on with the business of starting the engines. Battery switches on and magneto isolator button pushed in. The engines needed to be primed, so six strokes on the wobble pump behind my head whilst operating the priming switch on the overhead panel before switching attention to the start switch and the magnetos.

To guard against hydraulic lock the start switch is operated first through six blades before selecting the magneto−the starter motor has a clutch which disengages the starter if any resistance is felt.

Grumman G-21 Goose amphibious flying boatGrumman G-21 Goose amphibious flying boat

With the throttle cracked open the tiniest amount, the engine burbles into life as soon as the magnetos are switched on, so it’s time to select the starter to the other engine and repeat the process. Oil pressure checked and then sit back and wait for the oil temp to get to 40°C.

Burke used that time to talk about taxying as I was the only one with any brakes! As previously mentioned, the tailwheel is free to castor, so taxying is a combination of rudder, followed by brake, followed by differential power if necessary to keep the Goose from going anywhere it wanted to.

The tendency with newbies like me is to forget to reduce power on one of the engines before increasing power on the other to start a turn, which results in ever increasing power being used against the brakes.

My first challenge was going to be getting out onto the taxiway between the C185 on one side and the neighbour’s hangar wall on the other. With an engine, auxiliary fuel tank and float in the way, it was difficult to judge from the cockpit where exactly the wing tip was, but Burke assured me that we had plenty of room so, with the engines warmed we were off. The cylinder head temps were by now at the required 100°C so we carried out the standard checks on the mags and props and then it was time to head out onto the water.

Grumman G-21 Goose amphibious flying boatGrumman G-21 Goose amphibious flying boat

Burke directed me to the ramp and in we went. Once assured that there was clear water under the wheels (the linkages can be damaged if the gear is raised whilst still in contact with the lake bed) I cranked the gear up whilst trying to keep us going in a straight line with rudder, aileron and differential power.

The gear can be raised electrically, but this is only done after a runway takeoff. To ensure that no underwater debris has fouled the gear, it’s done manually after launching into the water, any resistance being felt through the handle.

To crank the gear it is necessary to first lift a pawl on the lower back bulkhead, then check that the pin that goes through the ratchet mechanism (again on the back bulkhead) is pointing towards the left seat pilot, thus ensuring that the gearbox is engaged for retraction, and finally wind that handle. A quick check both sides that the wheels are snug in their wells and the job is complete.

All this seemed to take forever while the aircraft was weaving across Lake Hood, but soon enough I was able to give my full concentration to our direction keeping, at which point I realised that I was still on the brakes trying to slow the Goose down! Luckily for me the wind was light so in maintaining the taxy lane at Lake Hood whilst travelling downwind the Goose was only marginally unstable. Without the brakes the only way to change or maintain direction if the rudder wasn’t doing the job was a quick burst of opposite engine power.

Grumman G-21 Goose amphibious flying boatGrumman G-21 Goose amphibious flying boat

Burke left me to it until we were nearing the end of the lake and then took control to demonstrate the first takeoff. We’d previously talked it through and Burke’s method is slightly different from some who fly the Goose, in an attempt to minimise the damage that the water spray does to the props.

(I was amazed to learn that the water spray can damage the props in the same way as stones can, and that this damage needed to be dressed out frequently to prevent it from necessitating an early prop change.)

A laborious takeoff

Burke’s take off method goes like this: control wheel held right back and full right aileron to counter the swing from the engines. The trim is set for flight and the elevator is heavy, so this requires wrapping the left forearm around the control wheel! Then up to 30in manifold pressure on the throttles, keep the nose up, keep the nose up and then slowly allow the nose to drop as the Goose rises up on the step, all the while keeping straight with rudder and levelling the wings as they start to want to fly.

Grumman G-21 Goose amphibious flying boatGrumman G-21 Goose amphibious flying boat

Once on the step, reach across from the throttles to flip the flaps down to 30° and then back to the throttles, advancing them all the way to takeoff power of 36.5in. It’s a little more complicated than simply whacking the power up to maximum−but if it saves the props from some unnecessary damage, I’m all for it.

As the Goose accelerates on the step you can feel when it’s ready to fly. A couple of skips and we’re airborne, at which point hold the aircraft to allow it to accelerate in ground effect and raise the flaps before transitioning to the climb attitude and setting 30in and 2,000rpm. If you’ve done it right you find when you take your first look at the airspeed it will be at 90kt.

Lake Hood is right next to Anchorage International and the departure heading west on the Water Lane takes us straight towards Runway 15/33. It was not in use as summer repairs were being carried out but we still eased into a right turn to parallel it on our way out to the training area.

The airspace is busy−not only from Anchorage International and Lake Hood (which also has a north/south hard runway), but Merrill Field, which is a large general aviation airfield on the eastern outskirts of Anchorage, and Elmendorf Air Base, a couple of miles to the north of downtown, which houses F-22s, AWACs, KC135 tankers and Hercules.

This is all deconflicted by the use of transit lanes and height bands, so when Burke gave me control at about 400ft he directed me to maintain a heading to keep us in our lane northbound and to level at 900ft to deconflict us from any inbound traffic to Merrill and Elmendorf.

I settled the Goose level at 900ft with 27in and 1800rpm and I found it to be a little heavy but stable and the elevator trimmer (a winder at the front right side of my seat) to be very effective. The view out of the front is good−not so the view out of the side. Once clear of the inbound lanes we turned west to get into an area where there is a large lake and some clear airspace above.

Before starting on landings, Burke had me climb to 2,000ft and carry out some steep turns and stalls, both clean and with flap. The Goose is benign in the stall, there’s plenty of warning and then the nose just nods forward. There was a slight wing drop with the clean stall, but I think that it was more a case of me not having the aircraft properly balanced than any tendency of the aircraft as, with a bit more attention, the stall with flap was straight ahead.

Grumman G-21 Goose amphibious flying boatGrumman G-21 Goose amphibious flying boat

Burke then had me set up for the first approach to the lake before taking control for a demo. Power back (first check of the gear position) to reduce the speed to 90-100kt and adjust as necessary to point just beyond the trees at the near end of the lake. Flap to 30° (second check of gear position) and props fully forward (third check of gear position).

Then we were over the water and Burke adopted the landing attitude and used power to control the rate of descent as the Goose started to run out of airspeed. I’ve done a couple of float plane training flights and the technique is pretty much the same.

Once on the water Burke taught me how to taxi the Goose on the step by keeping the power up to maintain fifty knots and using rudder, aileron and power to manoeuvre the aircraft. It was quite an exercise in co-ordination and Burke had to help out a couple of times when I wasn’t keeping up with the aircraft’s wanderings.

Then it was time for my first attempt at takeoff. Burke talked me through the procedure again and off we went. I must say that it went rather well, there was the initial physical effort of holding the control column back whilst getting the aircraft up on the step but, once there, it seemed quite stable directionally and I could feel the slight acceleration when the Goose made the transition from waterborne to airborne.

By the time I had cleaned up, set the power and established the climb I was roughly ten knots fast, but apart from that, not bad for a first attempt. Around the pattern at 600ft we went and I set up for my first landing, remembering to check the gear with the reduction of power, then with flap and finally with props fully forward.

I aimed just beyond the shoreline of the lake, made sure that the speed stayed at ninety, established the landing attitude and waited for the Goose to settle back on the lake. A slight increase in power cushioned the touchdown and we were down.

Burke had me keep the power up to maintain fifty and then back up to full power for the touch and go. Another pattern and touchdown, but this time we slowed to a stop, the Goose wallowing as we came down off the step−it was time for lunch!

Grumman G-21 Goose amphibious flying boatGrumman G-21 Goose amphibious flying boat

Having stopped the engines, we went through the cabin, opened the door and took the cool box out up onto the wing where we drifted whilst we ate our lunch. Not another soul was in sight as we sat up there for about twenty minutes in the middle of a lake in Alaska – surreal!

Back in our seats, we wanted to start both engines with as little gap as possible otherwise we’d end up going around in a circle. So this time we primed both prior to start up and quickly switched the start switch control as soon as the left engine had fired.

We taxied back to the downwind end of the lake and conducted another takeoff before turning towards Anchorage to get back to Lake Hood. We maintained 1,200ft until in sight of the lake and then commenced our let down.

This approach required a bit more concentration and precision as I had to carry out a curved approach onto Lake Hood to line up with the narrow landing lane. It must have been quite a sight for the folks who live on that side of the lake as the Goose swooped down with me trying to ensure that I put the aircraft down as close to the edge of the lake as possible.

The touchdown was in the right place, maybe it could have been a little smoother but I was happy enough with it. Then the small matter of trying to keep the thing heading towards the ramp whilst winding the gear down and we were back on terra firma. We weaved and waddled back to the hangar and I shut down.

All in all, a great way to spend a few hours learning new skills. Once it is flying, the Goose is stable and straightforward but like many vintage aircraft it has its idiosyncrasies, most of the difficulties occurring when manoeuvring on land or water.

I can only imagine what it is like trying to keep it going where you want to go in strong winds and choppy seas. But it was great to fly it. The guys at goosehangar.com have done a wonderful job in restoring this warbird and keeping it flying.

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