Beech 24 Sierra

The Sierra is one of the slowest retractables you can buy. But its comfortable and well-made, and owners like it.

If the Mooneys are at one end of the retractable spectrum (small inside, but very fast and efficient) the Beech Sierra surely must be at the other end (very comfortable, but awfully slow). When trying to describe the Sierra, words like sexy, good-looking, or speedy are not the ones that first leap to mind. Most would select adjectives more along the lines of dowdy, slow, and utilitarian, with a goodly measure of comfort thrown in. To be sure, no matter how you slice it, the Sierra will never be known for its mass appeal. Indeed, it might better be likened to an old woody wagon than to any sort of sports car.

And like the woody wagon, the Sierra has a certain appeal for those in the market for good, reliable air transportation that wont break the bank on either purchase or routine maintenance. It can handle surprisingly good loads, provides admirable comfort for its occupants and is pretty safe to boot. What it gives up in good looks and top-end speed, it pays back through these traits.

The Sierras roots lie in the Musketeer, Beechs attempt to create an airplane to compete with the Cherokees and Skyhawks of the world. The first of that line, the A23, hit the market in 1963. Three years later, the Model A 23-24 Super III debuted. It was not great shakes even then. With 200 HP and fixed gear, it certainly wasnt going anywhere very fast. Today, these aircraft should, by rights, be considered in the antique/classic realm. Their numbers are few enough to make them a conversation piece at any airport they happen by-provided, of course, that anyone recognizes them for what they are.

By 1970, Beech had made the decision to put folding legs on the Sierra. The Model 24R was born. The first version was dubbed the A24R. It gained a bit in speed, but still lacked some of the better, more utilitarian (there’s that word again) features that would make its successors much more likeable. It did, however, have the hallmark of all Beeches: it was comfortable (as in roomy) for the occupants. In a general aviation world where most designs crammed people shoulder-to-shoulder, this alone was a good selling point.

By the following year, Beech apparently thought to capitalize on the comfort aspects of the design. A second cockpit door appeared along with a baggage door on the left side. These made getting people and luggage in and out a much easier affair. No more struggling over seats or forcing passengers to lug baggage into the aft area.

The design remained fairly static until 1973 when the B24R rolled out. A new instrument panel featuring quadrant-style engine controls was the most visible change. But Beech also enlarged the baggage door a bit. Eventually, many people would discover that the baggage door could now be used to allow squirming children to get into the rear jump seat. Beech also swapped props with the B24R, going from the original McCauley to a Hartzell.

In 1977, the C24R was introduced. Last of the line (production ceased in 1983), the C-model featured some sprucing up improvements. New aileron bearings were used which made the controls feel smoother. The fuel tanks were changed to allow for more usable fuel. The cabin vent system was changed, improving what was already an excellent system by most owners reckoning. A larger-diameter prop was hung out front to provide a bit more thrust (the new prop was two inches bigger). A rather modest drag-reduction program was instituted and leading and trailing fairings were added to the main wheel wells.

Quite comfy
The Sierras cabin comfort has always been one of the designs better points. Owners tend to rave about it. Beech has always been known for building airplanes that didnt squash the occupants, and the Sierra was no exception. But there’s a price to pay for comfort, and in the Sierra as in so many other designs (like the Rockwell 112), the penalty for all that space is rather prodigious wetted area for the fuselage. This, in turn, translates into drag and plenty of it. The out-in-the-wind landing gear (perhaps semi-retractable is a good term for it) does nothing to help here, particularly on the A and B models.

If there’s one uncomfortable aspect of the Sierras its noise. Despite their capacious interiors, cabin noise levels are quite high. Anyone contemplating buying a Sierra would be we’ll advised to spring for a set of noise-canceling headsets to go with it, along with a four-place intercom system. Otherwise, as one owner complained, even earplugs and regular headsets are but a poor defense. As mentioned, the cabin heat and vent system has proven to be a good one as light singles go, though some might argue that no GA airplane has a good vent system. Despite the rather large windows, the vent system, especially on the later models, is capable of keeping back-seat passengers from frying under the summer sun. In winter, its able to get warm air back there, preventing cases of flying frostbite.

The Sierras are also known for having pretty good load hauling ability. Its possible to squeeze six humans inside and still get off the ground. Of course, two of them can be standard-sized adults (170 lbs) in the front seats, while the next two would have to be a bit more diminutive (a pair of svelte 115-pounders for the middle seats). The last two would, of course, have to be children who could sit on the jump seat. And theyd have to be small at that, tipping the scales at 70 lbs or less. Yes, you could get all six of them in there and still have enough load ability left to hoist 50 gallons of fuel (and remain within the CG envelope, too). There just arent too many nominal four-place airplanes that can do that realistically.

If youre not into emulating college phone booth pranks with your Sierra, you can still loft an awful lot of load. The rear compartment is rated to a staggering 270 lbs. And, unlike many other aircraft, thats not just a marketing number. Its entirely possible to toss that much back there with two adults up front. Unfortunately, the middle and jump seats will have to be vacant, but if youre ever going to have to haul Uncle Mortys antique cinder block collection, its nice to know you can do it with a Sierra.

It would be a temptation to point at the Sierra and comment that it comes up short in terms of useful load when compared to some other 200-HP retractables. And that would be a true statement, as far as it went. But few other aircraft in this class allow as much load flexibility as the Sierra. Having a high useful load is useless if the CG restrictions prevent you from taking advantage of it, or, as some aircraft do, the useful load winds up being a balancing act between fuel and actual load (you can either have full fuel and no load or no fuel and a full load). But the Sierras useful load is more of a real-world thing. Consider that an IFR-equipped Sierra can haul three adults, 60 lbs of baggage and full fuel. Or, if you wish, fill the seats, keep the baggage and still have more than two hours in the tanks.

Going somewhere? Whats your rush? Speed is not the strong point of these smallest of the retractable-geared Beeches. As previously discussed, the flip side of the comfort coin is drag. One owner, in love with his airplane but unimpressed by its speed, dubbed his bird an Airslug.

Consider other four-seat retractables. There’s the Rockwell 112. It, too, is known for its comfortable, roomy cabin. And also like the Sierra, its not know for getting there fast (though it is slightly quicker than the Sierra). The Piper Arrow, which has the same IO-360 bolted up front, is booked at about seven knots faster. Cessnas Cardinal, which also sports a Lycoming IO-360, can overtake the Sierra by about 11 knots. At the far end of the scale is the Mooney 201, which traded cabin space for speed and comes out 20-plus knots faster. And, as if any more of a comparison was needed, consider the Grumman (Gulfstream, American General, etc.) Tiger. With fixed gear, the seemingly unsophisticated Tiger, with only 180 HP under the cowling, will pass a Sierra when flown at full throttle.

So the Sierra isn’t going to get you anyplace fast. And its also not known for getting in and out of tight fields with any degree of aplomb. Some owners consider their airplanes to be fit for paved-runway duty only. Short grass strips are not an appropriate venue for the Sierra.

But, again, although the Sierra isn’t quick, it can haul a goodly load and keep it in the air for a reasonable amount of time. If your bladder is up for it, you can make up some of the lost ground by just staying up longer and getting to wherever with fewer fuel stops.

Like most all the Beech line, the Sierra is considered by most to be an absolute delight to handle in the air. The controls are light and smooth, and fluid handling through graceful maneuvers is a breeze. The controls make it handle like something much lighter while providing a smoothness normally found only in much larger aircraft.

All this is true, until you try getting the thing on the ground. While the Sierra may be slow in cruise, its pretty fast on landing. Vso is 60 knots, making for a fairly high approach speed. For comparison, consider that the Mooney 201, considered a hot landing airplane, actually has a stall speed five knots lower than the Sierra. Other competitors, like the Arrow, also have lower stall speeds (11 knots slower for the Arrow, nine slower for the Rockwell 112B).

So, your speed down final is a bit higher to start with. And speed control is absolutely vital in the Sierra. A bit too fast and shell float badly. At the same time, the authority of the stabilator can lead to some pretty wild oscillations and overcontrolling. Its not a pretty picture. Try coming down final a bit on the slow side and youre likely in for a hard nose-first arrival. That same stabilator that had so much authority when the airspeed was too high tends to run out of ability when the airspeed gets too low-especially at forward CGs. This generally results in a wheel-barrowing landing. On the other hand, if you get the nose up while the airspeed is too low, the sink rate makes for a hard landing.

Compounding all of this is the extremely stiff landing gear. The shock absorbing system consists of rubber donuts a la Mooney. These have never been noted for their give, and age does nothing to soften their disposition. As one owner cracked, I can count the number of greaser landings Ive made on one hand. (And this in more than 400 hours of flying the beast.)

If there’s a secret to getting good landings out of the Sierra, its carrying some power into the flare. A little throttle jockeying can go a long way towards making for a smooth touchdown, provided your airspeed is right on the money.

On the plus side for landings, the Sierras gear has an admirably wide stance. Crosswinds are easily handled with a crab to the flare and then dropping the upwind wing just before touchdown to straighten out the nose. Beware landing in a crab, though, because the Sierra is no stranger to groundlooping. At the same time, avoid coming down final in a slip (the airplane is placarded against slips of more than 30 seconds in duration due to fuel unporting problems).

Despite these vices, the Sierra is a most pleasant airplane, at least up until landing. The stall, though coming at a higher speed than the competition, is gentle and gives good advance warning. At forward loadings, its more likely to simply hunt the nose up and down with a prodigious sink rate, rather than snapping down.

One handling virtue of the Sierra is the great strength of the landing gear in flight. As a speed brake, gear-lowering speed is pretty close to cruise speed-you can drop them at up to 135 knots. If you need to get down fast, or slow down fast in an emergency, dropping the gear is a good way to do it.

One final point worth noting is that the Sierra makes a fine IFR platform. Its smooth and precise handling in the air make tracking the VOR or executing a hold easy.

Service history
We examined some 20 years worth of Sierra Service Difficulty Reports from FAA. There were few surprises (for us, anyway).

If the Sierras have any one troublesome system, its the landing gear. All sorts of mechanical mayhem was found, but we did notice some items that bear careful attention. Like the nosegear. If the SDRs are any indication, a most thorough examination of the nosegear should be at the top of every annual inspection list. Broken nosegear steering lugs, nosegear actuators that bypass fluid, cracks in the nosegear yoke, binding or broken nosegear downlock springs and so on all added up to indicate that the nosegear merits special attention.

The nosegear wasnt the end of the problems with the gear, though. The main gear had their share of problems, too. Watch out for broken rod ends on the main gear actuators, bad main gear actuator seals and main gear attach point troubles. And for any leg of the landing gear, make sure the gear rigging and wiring is checked annually. Reports of limit and indicator switches being out of rig or broken were rampant, and in at least a few instances a misrigged nosegear limit switch turned off the hydraulic pump too soon, leaving the nosegear unlocked so that it folded on touchdown.

Another trouble spot was the engine induction airbox. There were numerous reports of cracking of the airbox where it mounts to the Bendix RSA injector flange. The Bendix injector servo itself was noted for contaminants and corrosion in seven reports, indicating poor maintenance practices.One final noteworthy finding was a number of reports of sticking starter solenoids. The result of this malfunction is that the starter engages as soon as the master switch is turned on. The hazards for personnel around the aircraft are obvious, so be careful when flipping that master switch.

The Sierra has had it share of type-specific and shotgun ADs, but most of these are better than 20 years old and should long since have been complied with. The few most recent are: 89-24-9, aileron rod end bearings (see below); 88-10-1, replacement of boost pump; 87-2-8, inspection of the stabilator hinge; and 85-5-2, modify the guard on the fuel selector (this guard had been replaced as the result of a 1975 AD).

There are also a couple of noteworthy ADs on the prop. 91-15-4 calls for the replacement of cracked parts and the modification of the hub, and 77-16-1 mandated the disassembly of the prop and inspection of the blades.

Fine points
When searching for a good used Sierra, there are some points to remember, and to remind your mechanic of during the pre-purchase inspection. (And don’t even think of buying a Sierra or any other aircraft without a good, thorough pre-purchase inspection.)

One of the first things to look at is the front end. Examine the engine mount and firewall for evidence of a hard wheelbarrow. This is where the damage occurs, so a careful check is in order. Also examine the logs carefully for evidence of a gear-up landing.

For either of the above, there are some tip-off items to watch for. An unexplained engine teardown and/or prop overhaul should raise immediate red flags. An FAA Form 337 stuffed in the books that lists only part numbers is another favorite gambit. And any airframe repair should be thoroughly investigated.

Another item to look for in the logs is replacement of the aileron rod end bearings. Over the years there have been many instances of these bearings seizing, leading to stiff or even frozen controls. Ultimately they became the target of the latest type-specific AD, 89-24-9, which calls for in installation of inspection ports and the inspection of the bearings. If the bearings havent been replaced, consider doing it shortly after you buy the airplane even if theyve been serviceable.

Yet another item to look for is engine hose age. If the hoses are ten years old or younger, theyre okay. Ten to 15 years and theyre getting old. Any hose older than 15 is a candidate for immediate retirement. Hoses are not cheap, so make sure the ones on your prospective purchase are youthful enough to pass muster.

Owner comments
I purchased a 1975 Sierra in 1993 after completing my private pilot program. Sierras are a great value with reasonable speeds when compared to other planes in their price range. insurance was about $1,000 for a zero time pilot, but retractable time builds faster towards lower insurance premiums.

I average about 135 knots TAS at 75% power, burning about 11.5 GPH. This is after installing the higher efficiency modified wing tips and Beech wheel well fairings, an improvement of about seven knots.

Overall comfort is excellent due to the cabin size, although ventilation is barely adequate in the summer heat due to the window heat buildup. I found the addition of a Kool Scoop a great help, but only for the pilot. Despite years of neglect, the airframe has held up very well, and only minor repairs were required to restore it. My Sierra was no exception to leaks when parked in the rain and most avionics in the aircraft have had to be serviced. After much research, leaks come from cracked drain tubes on each side of the windshield, allowing water to run along hoses and wires. Replacement of the windshield was also necessary in my aircraft to stop the leaks.

Although I went with the thicker windshield to reduce noise levels, I find no noticeable difference compared to the stock windshield.

Greaser landings are tricky due to the rudder/aileron interlock, which requires standing on the rudder pedals. Also, rudder authority is not as prominent as in the Cessnas. Ground handling is best done by using a combination of power and braking, as nosewheel steering is not efficient.

Having completed my instrument rating, I find the Sierra great for both training and short- to medium-length cross-country trips. The 200 HP engine and 1,000 pound payload allows about four hours fuel plus three to four passengers comfortably working and climbing within the ATC system at practical altitudes of about 5,000-9,000 feet.

Paul Hsu
Newark, N.J.

I own a 1974 Sierra. I like the large cabin and the large luggage door, along with the pilots door. The aircraft has good visibility because of the wings being located further back, and the windscreen is large and unobstructed.

Control response is good at lower speeds, although we added the Demer droop tips. These firmed up handling on slow approaches and improved landing and takeoff roll by about 10 percent. This improvement came at the expense of some comfort in turbulence. Weve noticed no increase in climb or cruise speeds. Stall speed was slightly reduced.

The airframe is Beechcraft rugged. It carries a nice payload but needs a little more muscle to handle it.

On the down side, it seems slightly underpowered at gross weight. Its real service ceiling is about 10,500 or 11,000 feet MSL.

The nosegear is weak, especially at the turning pivot. Turning during taxi is difficult because the pedals are so stiff. Ive spent more on the landing gear system that I should have. About $500 a year for the last three years. This has been for things like O-rings, check valves, new hydraulic pump motors and so forth.

Beechs parts prices have become completely unreasonable. An example is the plastic door latch and handle assembly which costs $410.

The cabin is noisy, due in part to the three large doors and the nine windows.

Jim Wrighter

For the past six years, I have been the happy co-owner of a 1979 Sierra. Having previously owned a Piper Warrior, an Archer, a Beech Duchess and Skipper, I have found the Sierra to be the most enjoyable aircraft of the group to fly. Perhaps most important, it has proven to be an excellent overall plane that does a commendable job balancing the compromises among speed, payload and comfort to total ownership and operating costs.

There are faster planes in the 200-HP class; however, they lack the comfort and convenience the Sierra offers. Compared to its competitors on the used market, the Sierra is a real sleeper, making it a good value for the money. It is fast enough to be a good cross-country machine, yet economical enough to justify using for local pleasure flights.

Six years ago, when our partnership came together and began the quest for a suitable aircraft, we selected the Sierra over the Piper Arrow, Rockwell Commander and the Mooney offerings due to the Sierras user friendliness and affordability. It is at least $5,000 less expensive than a comparable year-model Arrow. The cabin is second only to the Rockwell Commander 112 in roominess and passenger comfort. It has an excellent cabin ventilation system, especially with the optional cabin vent blower that keeps all on board reasonably comfortable once underway.

The two cabin doors make passenger loading quite simple. The baggage compartment door serves as a third exit. The presence of multiple exits on opposite sides of the fuselage could be handy in the event the flight comes to an untoward end.

Also, the baggage door is the largest in its class. The sheer size of the door permits loading of luggage from the floor upward in the cavernous baggage compartment. Conversely, the small hatch on the Arrow and Commander force the pilot to tote luggage over the rear seats after placing only a few articles on the compartment floor through the baggage door.

The plane benefits from simple straightforward systems and is easily maintained by a competent mechanic. The Lycoming IO-360 engine is one of the more bulletproof of the four-cylinder piston offerings in general aviation. With a 2,000-hour TBO and good fuel economy, it is reliable and trustworthy.

The electro-hydraulic landing gear is a proven system with a foolproof emergency gear down procedure-release the hydraulic pressure and the gear falls down. Most components are easily reached, helping to simplify inspection and repair.

The Sierra has very predictable handling and control response. It is a stable instrument platform and handles mild turbulence quite well. With partners of widely diverse backgrounds and qualifications, it made a good choice as a step-up to high performance for some of the group and satisfied the need for speed of the others.

As the top of the line single-engine airplane produce by Beechs Liberal, KS plant, the Sierra benefited from the evolution of the Musketeer and Sundowner lines. The plane retains Beechs reputation for strength and quality. One only needs to look at the size of the main landing gear struts and the cabin roof support braces on the edges of the windshield to see the rugged design built into the plane.

It was built to withstand the rigors of transition training and rental activities in the Aero Clubs operated by Beech dealers in the 1970s. This stout construction serves the owner-pilot well.

The metal instrument panel and cockpit layout us among the best in general aviation. It has room for most any avionics one would care to install in this class of aircraft. Early models had manual flaps, similar to those used on the Piper singles. Electric flaps were optional, with flap and gear switches conventionally located. The throttle quadrant on later models benefits from push-over levers instead of the push-pull knobs.

It would appear that the Marketing Department wrote the weight and balance section of the Sierras POH and flight manual. The manual lists the empty weight as 1,720 pounds. Our particular aircraft has an empty weight of 1,852 pounds. With a gross weight of 2,758 pounds, our payload is 906 pounds, or four FAA-sized 170-pound people, and 226 pounds (37 gallons) of gas. Thats enough for just over 2.5 hours endurance at higher power settings, plus a 45-minute reserve. On the other hand, we can fill the tanks with the 57 gallons of usable fuel, put in three FAA-sized people and 29 pounds of cargo and stay aloft for approximately 4.5 hours at higher power settings, with 45 minutes of reserve.

The plane will deliver 140 KTAS on approximately 11 GPH, but at higher gross weights, its climb performance becomes rather anemic. The wide cabin cross section that makes it a comfortable plane for passengers leads to a sizeable airframe frontal area. This, combined with sizeable flaps hinge brackets, stout boarding steps and assist handles, plus the elementary wing design, results in a large amount of parasite drag for the engine to overcome.

Besides the aforementioned lack of blazing speed, the plane suffers from two Achilles heels. The doors close by simply slamming them shut. There is no secondary latching mechanism as there is on the Piper Arrow. Doors popping open at rotation as the pressure above the wing decreases is a frequent occurrence if the door is not securely closed before takeoff. Efforts by the pilot to close the door tightly by slamming it hard only serves to compromise the integrity of the door hinges, further exacerbating the problem. Use of the top of the door as a support for entering and exiting the plane also places undue strain on the door hinges and serves to place the door out of alignment. Most passengers fail to properly secure the door on the right side, making verification of its security mandatory immediately prior to departure. Despite the manufacturers handbook statement that an open doors does not negatively affect handling, the noise, vibration and added drag do affect performance of both pilot and plane.

The outward-retracting main gear is the first of several idiosyncrasies of the landing gear. This configuration allows the Sierra to retain the inboard fuel tanks of the Musketeer and Sundowner line. Other than looking odd while in transit, it has no real bearing on the aircrafts performance. Fairings on the leading and trailing edges of the main gear wheel-well openings-characteristic of the C model-are the most significant aerodynamic improvements made during the evolution of the plane.

The use of rubber donuts rather than oleo struts is another of the landing gears quirks. The donuts do not absorb high loads as we’ll as oleos do. In fact, they seem to reflect energy. A hard landing can find the unsuspecting pilot projected back into the air at minimum controllable airspeed. A proper main-gear-first touchdown is mandatory. A nosewheel-first arrival can result in an oscillation of such force that the collapse of a gear can occur. The stiffness of the donuts causes the plane to hobby horse when taxied on rough pavement at any appreciable speed. The best way to stop the harmonic is to come to a complete stop and then resume taxiing at a reduced speed. These donuts need to be replaced periodically, and the donuts on both main gear should be replaced at the same time to keep the airplane level on the ramp and predictable on landing.

Of paramount importance, the spring on the main gear also requires frequent inspection and periodic replacement. As these springs lose their tension with age, their ability to hold the gear in the over-center position decreases. A hard landing with a side load can overcome their role in holding the gear extended, leading to a gear collapse-a situation that we had the misfortune of learning firsthand.

Also, one must keep in mind that an airspeed sensor, rather than squat switches, prevents inadvertent gear retraction while on the ground. Accidental selection of gear up while rolling out with any discernable airspeed can result in the gear coming up despite the plane being firmly on the ground. An instrument panel placard advising the pilot to raise the flaps to increase braking effectiveness may have led more than one pilot to grief. It seems that the policy of touching no switch until clear of the runway is as important in this airplane as in any other high-performance aircraft, the placard notwithstanding.

The unusual 90-degree rotation of the nosegear during retraction and extension makes it an aeronautical Rube Goldberg device that merits extra attention during inspections and preflight.

When the fuel tanks are full, the fuel gauges stay on the peg until at least an hours worth of fuel has been burned. As a result, they are quite accurate at lower quantities.

Product support from Beech has been excellent, with a good turn-around time for parts. The tail cones on the Sierra are notorious for cracking. It is noteworthy that the strength and integrity of replacement tail cones is not as good as the original part. As with all other parts these days, and Beech parts in particular, they are fairly expensive. The commonality of the Sierra and Sundowner line, plus the sheer numbers of Sierras and Sundowners produced, has resulted in the availability of a good supply of used parts. The systems are still supported by their manufacturers, making overall maintenance reasonable.

The Sierra Newsletter, produced by Walter Hake (710 Oxbow Lane, Barrington, IL 60010) offers some good preventive maintenance tips. For his annual subscription price of $12, it is a good value.

Our Sierra has been such a source of pride for the partners that we have lavished extensive attention on it. Following a landing accident, we elected to have it repainted by Downtown Airpark of Oklahoma City, OK. It was expensive, but Ron Troxell and his crew did a superlative job. Their attention to detail, plus a replacement interior, made the plane look better than new.

As we approach the engines TBO, we look forward to using High Performance Engines of Mena, AR, to do an engine rebuild with their porting and polishing blueprint engine process. A recent accident involving one of their key personnel has put a crimp on their scheduling, but we hope that they will have these problems resolved by the time we are ready for their services.

Just like pilots, no plane is perfect. However, once one understands the peccadilloes of the Sierra, it is truly a pleasant plane to fly and an affordable one to own.

Alan J. Beason

Also With This Article
Click here to view charts for Resale Values, Payload Compared and Prices Compared.
Click here to view the Beech 24 Sierra features guide.