The following report was copied from the Aviation Consumer used airplane guide printed in 1989. The prices in this edition are out of date of course.
The macho aura that used to surround double-breasted airplanes has pretty much faded away into aviation's folklore, but the two of everything afforded by light twins remains a powerful attraction to many pilots.
The Grumman Cougar is a rare bird that offers systems redundancy for operating costs that are nearly on par with those of high-performance singles, and it provides good performance and flying characteristics, to boot.
Owners speak in near reverence of the low maintenance requirements of their Cougars and the continued support of the orphaned airplanes by Gulfstream Aerospace. Though they worry about how long the support will continue, there seems to be a good supply of parts for the airplanes, at least for the near future.
The Cougar's relatively good, economical performance and forgiving flying characteristics also are points of pride among owners. They note that the airplane is nearly as fast and efficient as the venerable Twin Comanche with none of that light twin's control problems, particularly the Piper's tendency under certain loading and asymmetric power conditions to enter a flat spin. Indeed, some flight instructors believe that, because of its docility, the Cougar is unsuitable as a multiengine trainer; it just doesn't have the bite to give students a proper glimpse of the potential white-knuckle experiences in multi-engine flying.
Into the Void
Grumman American's announcement that it was developing a light twin from scratch came late in 1974, two years after the demise (some would say premature) of the popular but quirky Twin Comanche. A Cougar prototype flew early in 1977 and won its type certificate in the fall. Deliveries of the Model GA-7 began in February 1978.
The Cougar was on the market only seven months before Grumman American Aviation Corp. was purchased by Allen Paulson of American Jet Industries. Paulson made no bones about the fact that he had bought the company to acquire suitable facilities and trained workers to build his dream plane a weird bird called the Hustler, which had a turboprop engine in the nose, a jet in the tailcone and ultimately, went nowhere.
The Cougar's single-engine stablemates (the TCat, Lynx, Cheetah and Tiger) immediately were given the axe, but the light twin received a brief reprieve. All told, the Cougar remained in production for only about two years, and only 115 of the airplanes rolled off the assembly lines at Savannah (71 in 1978, 44 the next year). At last word, the sleek cats generally were fetching prices in the $35 000 to $45 000 range. Of course, you could pay less for a much-used-and-abused trainer that has been parked outside in the sun and rain all its life and still has the original Narco radios in its panel. On the other hand, we saw one pampered and unusually well-equipped Cougar whose owner hinted that he might sell if someone waved $60,000 at him.
Points of Departure
Grumman American and Beech Aircraft Corp., with its Duchess, were head-to-head in the race to deliver a new light twin in the late 1970s, and Piper Aircraft Corp. was hot on their heels with the Seminole. Eventually, these airplanes, too, would have truncated production runs; but both the Duchess and Seminole outnumber the Cougar more than three to one.
In several ways the Cougar is different from the other two light twins. Rather than having lapped and riveted skins, The Cougar's is bonded to the bulkheads and ribs forming its fuselage, empennage and wings The result is a slicker airframe, a much smoother appearance and, as reported by owners, fewer problems with corrosion. In addition, the lower portions of the cabin fuselage are made of strong but lightweight aluminum honeycomb. But the biggest difference is, of course, the Cougar's 160-hp Lycoming 0-320 engines. The Duchess and Seminole have 180-hp O-360s. They also have counter-rotating propellers, which eliminate the critical-engine bugbear. Both of the Cougar's props turn clockwise; therefore, a pilot theoretically should have a tougher time dealing with a failure of the left (critical) engine, since the right prop takes a bigger bite and produces more asymmetric thrust than the left.
One Fan Fare
The Cougar, Duchess and Seminole are much alike in one area: single-engine performance. All three perform miserably after losing an engine on takeoff. The Cougar POH indicates that, at sea level on a standard day and at its gross weight of 3,800 pounds, the airplane will climb at about 200 fpm on one engine, if the pilot does everything right (cobs the good engine, feathers the bad, gets the gear and flaps up, and so on). If a 200-fpm rate of climb doesn't sound all that bad, consider the Cougar's single-engine performance another way: that is, in terms of climb gradient.
Under the conditions outlined above, the airplane will struggle upwards a mere 140 feet for every mile it travels over the ground. With their 180-hp engines, the Duchess and Seminole don't do much better. Their single-engine rates-of-climb and climb gradients are, respectively: 235 fpm and 166 feet per mile; and 217 fpm and 148 feet per mile. That meager performance comes under standard conditions; lose an engine in any of the airplanes on takeoff from Denver on a hot day, and the numbers likely would have negative signs in front of them. At gross and with one fan feathered, a Cougar will climb 50 fpm at 4,250 feet, maximum, under standard conditions.
In comparison, the single-engine service ceilings of the Duchess and Seminole are 6,170 feet and 4,100 feet, respectively. Good Manners Although it does not perform well on one engine, the Cougar has good control characteristics,due to a large extent to the airplane's huge tail. Vmca, the minimum control speed with an engine out, is 61 knots-two knots below stall speed with landing gear and flaps extended. Stall strips on the leading edges of the modified laminar-flow NACA 63A-415 wing cause the wing roots to stall long before the hps
We were given a demonstration of the Cougar's docile manners by Gil Stout of Flying Tigers in Marietta, Pa., a former Grumman dealer whose specialties still include Cougar sales and service. At 1,500 feet on a warm day, Stout shut down the right engine, feathered the prop and made a 4~degree turn into the dead engine. No problem. Then, he pulled the nose way up. The stall buzzer shrieked as the Cougar shook like...well, a wet cat. One wing dropped, then the other; but Stout was able to pick them up with the rudder each time. Meanwhile, we were sinking at about 500 fpm; but, throughout the demonstration, the airplane never gave any indication that it was about to do something nasty. Because of limited elevator travel, it is difficult to stall a Cougar without abrupt control deflection. There is a trade off, however. According to owners, a pilot making a power off landing with full flaps in an airplane loaded toward its the front seats. forward cg limit can run out of elevator authority in the flare and plunk down on all three wheels, especially if airspeed is a tad too high on approach.
Short-Field Standout
Despite this idiosyncrasy, owners report excellent short-field capabilities. One said he operates a Cougar regularly on a 1,490-foot grass strip. According to the POH, the Cougar can lift off and climb over a 50-foot obstacle within 1,850 feet; 1,330 feet are required for a landing over an obstacle. This performance is predicated, of course, on proper technique and on having both fans turning. Unfortunately, the Cougar's POH provides no data on accelerate stop or accelerate go performance. Such information is provided in Duchess and Seminole POHs, though. Taxing on crowded ramps and taxiways is a snap. The nosewheel can be steered with the rudder pedals to a deflection of about 17 degrees; beyond that, the nosewheel steering mechanism unlatches, and very tight turns can be made with differential braking and power.
Performance
Due to the normally aspirated, carbureted 160-hp engines, the Cougar delivers its best cruise performance down low. For example, the POH shows that in standard conditions at 6,000 feet, true airspeed is 156 knots at 75 percent power with a fuel burn of 16 gallons per hour when leaned to peak EGT. At 65 percent power, airspeed drops about 10 knots and fuel consumption about three gph. A total of 114 usable gallons of fuel can be carried in the wing tanks. That's enough for a little more than six and a half hours of flying at 75 percent cruise power with an hour's worth of fuel for reserves. Relatively high gear- and flap extension speeds help in slowing the slippery airplane in the terminal area. The gear and 10 degrees of flap can be extended at 145 knots, indicated. At 110 knots, the flaps can be lowered all the way to 30 degrees. Pitch changes are nearly undetectable when the gear and flaps are operated. The Fowler-type flaps are electric, and the landing gear are operated by an electrically actuated hydraulic pump.
Creature Features
Owners rave about the spacious cabin, which provides plentiful head and elbow room, and even ample leg room for rear-seat passengers. All four seats have lap belts and shoulder harnesses. Visibility through the large windows is excellent. The Cougar has two baggage compartments. A maximum of 175 pounds can be carried behind the rear seats, but loading bulky items through the 14 by 28 inch door might pose a problem. The rear seats also can be folded to accommodate up to 340 pounds of baggage. The other baggage area is in the nose and has a maximum capacity of 75 pounds. A 2~inch-wide door on the right side of the nose provides access to the baggage area, as well as to the battery and any electronics equipment housed there. The baggage areas and the large fuel tanks provide plenty of leeway in loading the airplane. Most Cougars have a useful load of about 1,230 pounds, enough for four passengers, their baggage and enough fuel for three and a half hours of flying.
Maintenance Considerations
As previously mentioned, owners report that their airplanes require very care beyond normal maintenance and inspections. However, one airworthiness directive requires overhaul or replacement of the Hartzell propeller blades every five years or 2,000 hours in service. Two other ADs require periodic inspection. and replacement of Bendix magneto blocks and paper induction air filters. In addition, the Cougar's type certification data sheet shows one life-limited component: the inboard wing spar assembly, which is limited to 5,705 hours. Parts availability seems to be no problem at present. Gulfstream Aerospace maintains a stock of Cougar parts. A company spokesman said that although a buyer still is being sought for the orphaned light airplanes, Guifstream will continue supporting the Cougar "as long as necessary." Other parts sources include Air Mods Northwest in Snohomish, Wash., Fletcher Aviation in Houston, Flying Tigers in Marietta, Pa., and Wag-Aero in Lyons, Wisc.
Only 33 service difficulty reports have been filed by Cougar mechanics in the past six years. Among them were several reports of cracked rudder bellcranks and elevator horns, deteriorated fuel transmitter floats and mulfunctions in the landing gear position-indicating system. In addition, Ken Blackman of Air Mods NW told us he found a badly frayed elevator trim cable while installing soundproofing in a Cougar's tailcone. He said the damage probably would not have been spotted during a routine annual inspection. Blackman also advised that prospective Cougar buyers should inspect the wheelwells carefully for rust. It appears that the wells in some of the airplanes were not primed correctly and can start to rust when water is slung into them by the wheels.
Poor craftsmanship reportedly led to paint problems on many of the AA-1, AA-5 and GA-7 airplanes that were built in Savannah. "I rejected one airplane three times until the factory repainted it" one former dealer recalled. "It looked as if a drunk had laid out the stripes. And I have seen paint chipping off many of the airplanes Grumman American made."
Safety Record
At press time, NTSB had only two Cougar accidents in its files for the past seven years. One airplane aashed into Corpus Christi Bay, killing all four people aboard, during a night business flight in May 1980. The airplane was never recovered, and the probable cause of the accident remains undetermined. The other accident occurred in November 1982 in Nebraska. The Cougar was on an air taxi flight with two people aboard when it struck trees and crashed in a meadow during a VOR approach. The crash occurred on a dark night with a 200-foot, obscured ceiling and six4enths of a mile visibility in fog and drizzle. The pilot suffered minor injuries; his passenger was killed. NTSB determined that the Cougar had dropped below the published minimum descent altitude during the approach and was then climbing when it hit the trees.
A check of the FAA's records revealed seven incidents during the past seven years. One Cougar settled and struck its props on a runway when the pilot retracted the gear on takeoff; but the damage was minor, and the pilot was able to bring the airplane around and land. Another airplane was not aligned with the runway when it touched down on a training flight, and it ground-looped and struck a VASI light. One incident involved a Cougar that taxied into another airplane after being hand-propped. There were no injuries nor damage when another Cougar had a complete electrical failure on takeoff after having been jump started due to a dead battery. A broken gear-door hinge prevented the left main gear from locking on one airplane; the gear collapsed on landing, causing minor damage.
Another Cougar made an uneventful single-engine landing during a training flight in which a propeller would not come out of its feathered position. The last incident also involved a single-engine landing; the pilot had shut down his left engine after a broken connecting rod punched a hole in the crankcase.
Belling the Cat
Systems redundancy-and the peace of mind that comes from having two alternators and two pneumatic pumps while shuttling about at night or in weather-probably is the best reason to consider buying a light twin. And the Cougar seems to offer a lot of bang for the buck in this respect. In comparison, its more powerful contemporaries, the Duchess and Seminole, just don't seem to provide a sufficient edge on performance to match their higher acquisition, operating and maintenance costs. However, the Cougar is an airplane in limbo. Although owners paint a rosy picture of current maintenance needs and costs, that picture could change. There's no way of telling if and when Gulfstream Aerospace will pull the plug on supporting its orphan airplanes. If that should happen, current stocks of parts for Cougars could dry up quickly. And though the Cougar has earned an excellent reputation for its docile handling qualities, its performance on one engine is no better (and in some cases, worse) than any other light twin.
If you brush elbows with Cougar cognoscenti long enough, you're bound to hear of how so-and-so took off, circled the pattern and landed using only one engine. . Such tales, even if true, deceptively ameliorate the exposure to high risk that a pilot of any piston twin is subjected to between lift-off and 50 feet above the runway. Prospective buyers should keep in mind that an engine failure on lift-off would require flawless pilot technique and result in meager climb performance. Therefore, a prospective buyer would be wise to weigh systems redundancy against the relative merits of a sophisticated single, such as an A36 Bonanza or Centurion of the same vintage, which cost about the same on the used market but fly faster, burn less fuel and carry rnore payload. But, if you just have to have a light twin, the Cougar certainly deserves a close look.
Owners are supported by the American Yankee Assn., P.O. Box 11757, Fresno, Calif. 93774.
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Owner Comments
My partner, Norman Radin, and I have had our Cougar about six years now. We traded up from a Twin Comanche because we were concerned that the airplane was just getting too old. We were having difficulty getting parts, and the avionics needed to be upgraded, which would have been very expensive. When we decidedto trade up, we looked for an economical light twin. We looked at the Duchess and the Seminole and even considered an older one, the Travel Air. But we decided against the Travel Air, because I had owned a B-55 Baron earlier, and it proved to be a relatively more expensive airplane to maintain. The Duchess and Seminole did not seem to have the -extra performance that would justify the maintenance on their larger engines.
The Cougar I appeared to offer more value. We are very pleased with the Cougar. We had only one major problem in all the time we've had it, and that was damage to the rudder caused by a wind storm. It took a little longer than we would have liked to have the rudder replaced, but Gulfstream eventually came through with the parts. There was a problem at the factory, and it took about six weeks to get the parts. We also had a minor problem with water leaking into the nose baggage compartment. Other than that, we have had no problems. We have had very low maintenance costs on that airpian that unbelievably low. I usually fly between 8,000 and 11,000 feet, the most efficient altitudes for the airplane, as close to 75 percent power as I can get and lean it back to the economy range. Almost always, I make my filed airspeed, 155 knots, and burn somewhere between 15 and 16 gallons an hour. And that's very close to what we used to get with the Twin Comanche; the numbers are very similar in terms of performance. The Cougar is a much more stable airplane than the Twin Comanche and easier to fly.
When it came to landings, the Twin Comanche seemed to have a mind of its own; you just couldn't grease it on every time. The Cougar is a very forgiving airplane; it does just what you want it to do. The stall characteristics are very docile, and I really don't think you could spin the airplane, even if you wanted to. It's very light on the controls and lands very easily. It's also a wonderful instrument platform. Our insurance people told us the Cougar is the safest light twin flying, and they give a reduction in rates because of that. It is a true four-place airplane. You can load four people and their baggage, and still carry enough fuel to have good range capability.
The Cougar has a big cabin; it feels a lot like a Baron. You sit up high, and visibility is excellent. There's a lot of leg room, but, unfortunately, the rear seats don't recline. We like the systems redundancy you get with a twin; and we're going to stick with the Cougar, because there is really nothing else that compares with it. The only thing I don't like is that it has only one landing light, which is on the nose gear. Therefore, you can't always show a light when you want to. I wish someone would offer an additional, recognition light in the nose or wing.
Over all, workmanship and quality are on par with Piper and Cessna's airplanes, but certainly not up to Beech standards. The Piper Seminole is much smaller, and the Beech Duchess wags its tail in turbulence like a Bonanza and is a maintenance hog. The GA-7 is a large aircraft with room to spare in the cabin and rear-seat area, and it's fast. I trued out at 170 knots at 8,000 feet, firewalled with two people and half fuel on a cool day. At 24 inches and 2,400 rpm, it averages 145 to 155 knots. It does everything well on one engine, except climb fast. In 250 hours, 1 have had to replace both vacuum pumps (originals), and a starter solenoid stuck, broiling the starter. That was my fault for not shutting off the master switch after takeoff, but I needed my lights as it was a night flight. I've also installed new brake linings, new tires and a new strobe power pack. I used a Whalen, which works fine; the original Grimes would have cost three times as much to replace. I was plagued by absent and erratic oil pressure indications until I discovered the gauge cluster wasn't grounded properly and added a separate ground wire, solving the problem.
I've changed the oil filters and oil every 50 hours, using both Aeroshell and Phillips multi. During the past 100 hours, I've used Shell in the right engine and Phillips in the left; the airplane uses 10 percent less Shell, and the oil stays cleaner longer. I changed the lower spark plugs to a long-reach type, which seem to have solved a problem I had with fouling on lOOLL avgas. The plane actually has cost very little to own and maintain. It uses between 16 and 19 gph; and it is a pleasure to fly and easy to land. In my estimate, the Cougar is probably the best light twin ever built. Parts have not been a problem. Gulfstream Aerospace supplied plastk wing root fairings within two to three weeks and claims to be able to supply any other parts I may need. Wag-Aero and Dave Fletcher also have a good supply of parts, so I don't think there will be any worse parts problem with the Cougar than with any other aircraft.
As you may have guessed by now, I am very happy with my GA-7 and would buy another one. They are certainly a good value on the used market.
Other repairs to the aircraft were fairly minor. There was considerable wind noise from the door, so I had an FBO order and install a door seal. They put it on backwards, so I ended up doing the job over again. In addition, I had to have the struts aired, the wheel bearings repacked, the brake pads replaced twice and the sparplugs changed.
The Hartzell two-blade propeller has an AD that requires inspection or overhaul every five years.I had an overhaul done by Hanzell in Piqua, Ohio; the cost, including removal and reinstallation, was just over $2,000 Annual inspections, which I helped to do with the assistance and guidance of an A&I,cost$200peryear.I removeallinspection covers, the tail cone, engine cowlings, etc. The A&I merely had to inspect the various components. During the two years I owned the Cougar, I found the airplane easy to fly, stable and forgiving. The autopilot made cross country flying a breeze. I flew the airplane at 23 inches and 2,300 rpm, or about 70 percent power, because I found higher power levels substantially increased noise in the cockpit. Fuel consumption averaged 14 to 16 gallons per hour, and the aircraft burned about one quart of oil every 20 hours. Overall, it would be almost impossible to beat the Cougar in terms of reliability, economy and safety. It probably is the best "first twin" to own.
To date the only airframe parts we've put in have been tires, brakes, light bulbs and batteries. I still have almost the complete inventory of parts I was required to buy from the factory back in1977 to be a Grumman dealer. The only thing I've used out of that is one throttle cable so far. I've been in this business going on 30 years, and I've never had any problem getting Grumman parts. To be honest, the Grummans use fewer parts than any other airplane I've maintained. We use our own Cougar for multiengine training. It's got 2,000 hours on it and has never been in the hangar. The paint is chipped and faded; but, mechanically, it's excellent. We change the oil every 100 hours, put in a new set of spark plugs every 400 hours, replace the brake linings about every 200 hours and, occasionally, put in a new light bulb or battery; but that's it. It's got Lycoming O-320-Ds, which are just excellent engines. The Slick magnetos require no more maintenance than Bendix mags; except that, when they were introduced, they were a throwaway mag, and there are too many mechanics who still consider them as throwaways and don't take a good look at them, first.
The Cougar was designed from the beginning as a twin; the other so-called light twins are adaptations of singles. The Seminole is an Arrow they put two engines on; the Duchess is a twin Musketeer. The Cougar has a lot of things the others don't have. For instance, if you lose both the mechanical and the electric fuel pump in the right wing, you can keep both engines running by going to double cross feed. The pumps correspond to the tanks, not to the engines. When I get out of this business, I'm going to take a Cougar and rebuild it from the ground up to keep as my own personal airplane.