International Pilot Services - (1996) She's Not Done Dancin' --Lockheed's JetStar

In an age of leveraged buy outs, cost cutting and fractional ownership, corporate aviation careers are filled with periodic retirement, largely expected albeit unpredictable. At the end of one such chapter, two winters ago, an E-mail message arrived from a friend in Europe, "Want to fly a Jetstar?"

After flying corporate aviation's preeminent "big iron" for twelve years, I contemplated the response for a few days and thought, "I’m not an equipment snob, why not?"

My transition to four engine flying began almost immediately at Flight Safety in Atlanta. Our initial class was shared with the entire staff of the Lithuanian government's VIP squadron. As former Soviet States sought to modernize and economize their VIP fleets, they too recognized the inherent value of the aging but effective Jetstar.

The Jetstar was the brainchild of the aeronautical genius, Kelly Johnson--designer of the Lockheed’s P-38 Lightning, Constellation, U-2, SR-71, and other wonder machines. It is also the only corporate jet ever manufactured by a major airliner company and defense manufacturer. The owner of this particular Jetstar accurately refers to it as “the DC-3 of corporate jets.”

The decision to build a small transport jet in the 1950’s was no easy choice, given the limits of technology and costs. The US Air Force generated two requirements to modernize it’s fleet of wartime utility transports (UCX) and multi-engine crew trainers (UTX) yet had no funding to sponsor a development program. The Air Force informed industry that if the budgetary restraints were lifted, it would purchase any flight-proven aircraft meeting its specifications. Both Lockheed and McDonnell chose to respond to the heavier UCX requirement.

Once company approval was granted, Kelly Johnson’s team designed, assembled and flew the new aircraft in eight months. That prototype flew, in late 1957, with only two Bristol Orpheus engines and without the now characteristic slipper tanks on its wings. (That original prototype can be seen on the ramp in Vancouver, BC --CYVR) In the three years that followed, the engine configuration changed due to Air Force unwillingness to purchase an airframe with foreign built engines. Accordingly, four Pratt & Whitney JT12A-6’s were fitted to the second prototype which had already been fitted with then “optional” slipper tanks intended for longer range operations. By the time the US Air Force committed to order the Jetstar, Lockheed carried conditional orders for more than thirty airframes. McDonnell’s contestant for the UCX role failed to gain any orders and eventually even they purchased and operated the Jetstar.

Throughout its interrupted production life, the Jetstar saw four basic configurations. Another colleague of mine is one of us few younger pilots lucky enough to have flown the Jetstar and has experience on all four models. Frank Radvany recalls, “The original -6 was indeed underpowered. It seemed to take forever to reach eighty knots which was not too encouraging with the end of a runway rapidly approaching.”

The original -6 was replaced after ninety seven airframes by the -8, the difference being upgraded JT12A-8 engines. The -8 thrust increase was ten percent per engine which improved takeoff and climb performance considerably. Fuel burn remained a problem and many old timers would start and taxi the aircraft on two engines in an effort to conserve the precious stuff. Amid skyrocketing fuel prices, Jetstar production was suspended in 1973 with sixty-six -8’s delivered. Both Lockheed and AiResearch were working on turbo fan variants of the Jetstar to improve consumption and increase range. AiResearch’s Jetstar-731 retro-fit was the first to fly in 1974, and reenergized the market by upgrading -6 and -8 models. Lockheed’s new Jetstar II, with slight improvements to the original design, was introduced nearly two years later. Both programs were centered on the Garrett 731 turbofan.

Jetstar production ceased, in 1980, with the delivery of five VIP aircraft to Iraq and more than two hundred airframes built. Throughout that production run Lockheed maintained an enviable claim to have been the choice Head of State aircraft from the US through the Middle East to Indonesia. One can only speculate what might have followed if Lockheed had not encountered financial problems.

Relative to the closest comparably priced business jet, the Falcon 20, the Jetstar looks very good indeed.   Similarly priced models of the Falcon 20 are equipped with the older Stage II, General Electric engines. These Falcons, typically around two million dollars, will increasingly encounter difficulties operating at noise sensitive airports and have a range of about 1300 nautical miles. The Falcon 200 or the Falcon 20, re-engined with Garrett -731 engines are quieter and have a range of about 2200 nautical, although the purchase price doubles to over four million dollars. With any engine, the Falcon purchaser gets a seven hundred cubic foot cabin that he can’t stand up in.

On the other hand, the Jetstar owner buys 850 cubic feet of cabin volume or twenty percent more than the Falcon’s. Despite the lower overhead of the Jetstar's entrance, it quickly opens to a trough aisle that remains flat to the aft pressure bulkhead and nearly half a foot higher than the Falcon 20, 200 or even the 50.

Garrett 731 equipped Jetstars trade in two distinct ranges, a lower one for older airframes re-engined with the Garrett and a higher range for the newer Jetstar II. At present the older Jetstar -731 is trading for $1.2 to $1.7 million while the Jetstar II commands $2.2 to $2.4 million. At these prices either model brings to market the range and stand-up headroom unequaled by any other competitor including the Falcon 50, trading between $7 and $14 million. The difference in capital cost alone is sufficient to fund the additional maintenance required by the Jetstar’s older airframe. Expressed in defense parlance, "It's the most bang for the buck."

However, on two issues, the jury is still out--noise and RVSM. My Jetstar recently received Stage III noise certification which makes it more useful than our Gulfstream III. While the reduced noise certification should enhance value, the impact of unmitigated North Atlantic RVSM operations and the reluctance of Lockheed to support the remaining fleet may well exclude one of the most capable aircraft from the “ETOPS Pond”. Don’t think for a moment that the RVSM issue will not be a prickly one for the Falcons, including a number of older Falcon 50’s.

Intermittently during training, I struggled to comprehend this B-29 technology strapped to a five hundred mile an hour airframe. I honestly believe that only the Olympics involve more relays than a Jetstar. At those moments another Jetstar veteran and mentor admonished me, "Forget about technology, enjoy the machine."

Jack and his retired Air Force buddies had long praised the Jetstar, adopting in the recollection, a goofy look usually reserved for first girlfriends. I had long since written off the stories to the excesses of time and inaccuracies of memory.

“Those guys are nuts!”

Simulators are not always helpful in duplicating handling qualities and the extreme age of the sole Jetstar simulator only amplified that shortcoming. The limitation was more than offset by the unparalleled experience of the Flight Safety instructors. Still, little could have prepared me for my first "handful" of Jetstar. I was only days out of a Part 135 check on the Gulfstream IV--my then favorite aircraft and a tough act to follow.

At first glance, the cockpit seems daunting. With so many dials and levers it looks more like a U-boat than a business jet. Just getting into the Jetstar’s cockpit is a science, the difficulty directly proportional to the length of the pilot. The pedestal is long and the overhead panel low, punctuated with protruding switches and controlers to lacerate your scalp. Entry requires a healthy stretch of the outboard leg and prudence to your head as the inboard leg is brought along. Once seated, the visibility is very good with a total of nine windows. That includes two overhead windows--a wonderful tool in circling approaches.

On one point, my friend Frank and I disagree. Ergonomics was a word known only to Latin professors at the time the Jetstar was designed. Frank has thousands of hours in the Jetstar and has deciphered logic in the location of switches and instruments which I feel were pitched into the cockpit from a distance. In the plusses column, my Jetstar had better avionics than many Gulfstream II and III's. With dual UNS-1A's, GPS, AFIS and Pro-line radios it is a sensibly outfitted business power tool.

Unfortunately, someone once commented that the Jetstar was the only corporate jet that needed no door lock. Logic was that once inside, it was extremely unlikely anyone could get it started. There are nine circuits required in order to start an engine.

Those pesky relays, they’re everywhere!

There are enough things to remember in starting the small herd of engines, that I choose to remind myself of them in a real-time commentary that sounds like a Budhist mantra. Sound operating practice dictates starting inboard engines first since they are the only ones powering the hydraulic systems. Several Jetstars have been started with outboard engines first only to roll forward unchecked into obstacles.

Once the engines are started, systems checks remind me again of the relatively poor cockpit organization. Most remaining Jetstar cockpits have been improved over the years although items like the nose wheel steering positioning remain, understandably, unchanged. Taxiing the aircraft in close quarters can invoke carpal tunnel syndrome and the leaning stretch required to reach both nose steering and throttles during takeoff feels more like tai chi than flying.

A storm had just swept over Europe leaving clear skies and winter gales in its wake. We departed Luton, England for Geneva, electing to perform local training at the quieter Lyon-Satolas airport in France. With a headwind exceeding forty knots the takeoff roll from Luton was appropriately brief. True to its legend, the Jetstar seemed to slip into the sky as smoothly as an otter to the sea.

Hey, maybe those guys weren’t nuts!

This wing is at its best in the lower altitudes despite takeoff and landing rolls longer than more modern machines. Initial climb is strident even if one engine is failed or anti-ice is required. Stability is obvious with the first turns. It seems that the slipper tanks and large full flying tail are certainly contributing factors. A small negative byproduct of the flying tail is pitch sensitivity when hand flying at speeds greater than 270 knots or about M.70. The problem was only noticed in hand flying and easily mastered in a few dozen hours.

Noise levels in climb are noticeably higher than newer aircraft but still tolerable. Climbing above twenty five thousand feet requires time, speed and distance. Failure to maintain a speed of at least M.70, usually doubles the time to climb. Plan on initial cruise levels between FL330 and FL350 and be patient. Step climbing is essential to optimize the range of the aircraft and although the performance manual may include data for FL430, it’s hard to imagine how anyone ever got there. The non-critical wing was designed by engineers who had limited experience above thirty thousand feet.

My friend and co-worker, Vassilis, taught me to level off at each new altitude and set one thousand pounds per hour fuel flow per engine until the desired cruise speed is reached. If the aircrafft is heavy or the ambient temperature above ISA, climb and level-off fuel flow must be adjusted to not exceed TGT limits. His method ensures that cruise flight is not sustained in an inefficient climbing attitude.

The optimum cruise fuel flow, about 700-800 pounds/hr/engine, yields a stately M.76 cruise and an unholy noise level. Kelly Johnson was breaking new ground in aerodynamics, not in cockpit acoustics. The M.76 cruise delivers an average endurance of five and a half hours or approximately 2200 nautical miles in still air. On short flights, cruise speeds of M.80 are possible although you will likely spend the rest of your life watching closed caption television.

For me, the most challenging system on the aircraft has been the fuel system. After a lifetime of twin engine / twin tank flying, the permutations of four engines, six tanks and more valves than refinery nearly drove me to a straight jacket. More accurately, it perhaps drove my crew members to putting Me into one. Until reinforced by several hundred hours of practice, there were numerous occassions on which I verified the autopilot’s aileron trim limits. Conversely, once mastered, there is virtually no limit to the routing or distribution of fuel--an amazingly flexible system.

Getting the Jetstar down from altitude is an art.   With four engines operating, my preferred technique, is to slowly idle the outboard engines then reduce the inboards to about 80% N1 (Fan) while starting a gentle pitchover. This provides not only acceptable cabin noise levels (under M.80) but also ensures adequate pressurization. As with most old airframes, the leak rate is formidable as seals and fittings loosen with age. The bleed air available from four idling Garretts simply isn’t enough to maintain cabin pressure in the descent.

Approaching the airport, the aircraft must be slowed to 200 KIAS for flap extension. A higher flap extension speed would be nice but so would winning the lottery. Several old-timers routinely push the flap limit to its maximum or beyond--something not recommended with any airframe, much less one thirty years old. There are only two non-clean flap settings, “Take-off/Aprroach” and “Landing”. For either setting, a leading edge flap is extended outboard of the slipper tank along with one of two stages of fullspan trailing edge flaps. Deceleration isn’t easy with two engines at 70 to 80%. Since further reduction on the inboard engines causes a loss of pressurization, my preferred method is trailing the speedbrake. This simply unlocks the table sized door which doubles as a ground access ladder for the aft equipment area. The aft fuselage location causes no noticeable pitch change or cabin noise unless fully extended and the trail position nicely looses the excess ten to twenty knots for a comfortable flap extension. As flaps move into position, simply stow the speedbrake while bringing the outboard engines up to match the inboards. The aircraft is in perfect shape to transition to the approach.

The Lyon ATIS reported winds gusting diagonally across the runway at thirty to forty knots. Turn to final was accordingly long and landing configuration accomplished at six miles for my first landing. With the selection of landing flaps and a slight power increase on all four engines, the aircraft assumed the desired attitude with the steadfastness of a knife plunged in peanut butter. Despite the seeming rock solid stability nothing more than a nudge of any control was required to compensate for the rollicking winds.

Crossing the threshold, all throttles were closed. Even a strident descent is naturally arrested by ground effect and the slightest back pressure assures a nearly flawless touchdown. Subsequent takeoffs, landings and engine out work were as impressive as the first.

Failure of one engine results in a polite rudder kick, just enough to let the pilot know something is different. Performance isn’t really degraded until a second engine is failed. In simulator training a third engine was failed in the process of returning from a two engine out scenario. Although I felt the little Garrett was operating at hemorrhage power, the remainder of the very abnormal approach was a wonderful confidence builder whose veracity will likely never be tested.

Throughout all phases of flight the Jetstar demonstrated an uncommon balance of maneuverability and stability. In the two years since that first landing, I have found the Jetstar to be unquestionably the finest handling aircraft in my experience. It makes bad pilots look good and good pilots look God-like. Wherever Kelly Johnson is now, we share a knowing smile with each and every landing.

“Those guys were right!”

Wearing her age like elegance, the Jetstar may not be the belle of the ball; but, with 731's, decent avionics and a standup cabin for two million dollars, she’s not done dancing.

Specifications:

Wing Span (ft)                                    54’ 5”

Length (ft)                                           60’ 5”

Max Gross Take-off Weight           44,250 lbs

Typical Basic Operating Weight    26,200 lbs

Max Fuel Allowable                      18,850 lbs

VMO / MMO                      350 KIAS / M.82 > 26,000’

Cabin Height                                          6’1”

Cabin Width                                          6’2”

Cabin Length                                       28’2”

Cabin Volume                                 850 cu ft

(Data courtesy of Hallmark Aviation)

Author’s Bio (1996):

Roger Rose, is a pilot of twenty years international experience and ten thousand hours soley within corporate aviation (ATP, GIV, G1159, L1329, DA20, F27 and G159). He is employed by International Pilot Services, Inc., of Palm Beach Gardens, FL. He has just completed a project to integrate aviation oriented CRM training into an Athens (Greece) based fleet of tankers and hydrofoils.

Last Updated ( Wednesday, 22 October 2008 )

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