The “Twin Cat” of the late 1970s and early ’80s was one such example. A development of the 1950s-era, purpose-built Grumman Super Ag Cat biplane, it replaced the Ag Cat’s single 600 hp Pratt & Whitney R-1340 radial engine with two 310 hp Lycoming TIO-540 flat-6 engines.

Rather than being offered as a complete, factory-built aircraft, the Twin Cat was a modification offered in the form of a supplemental type certificate (STC). The Twin Cat Corporation targeted Ag Cat operators wishing for more easily serviceable engines with increased overhaul intervals and multiengine redundancy, and the company offered to travel to the customer for on-site modification of their Ag Cats.

The company had some impressive experience at the helm. The president had overseen the development of a turboprop conversion of the Grumman Albatross and was assisted by the former chief test pilot at the general aviation division of Rockwell International. Most of the test flights were flown by Herman “Fish” Salmon, retired chief engineering test pilot of Lockheed. Salmon had conducted spin testing of the P-38 Lightning and had flown the first flights of the L-188 Electra, P-3 Orion, YF-104A Starfighter, and XFV-1 turboprop VTOL fighter. 

When designing the Twin Cat, one of the top priorities was to minimize asymmetric thrust in the event of an engine failure. The team did so by utilizing an unconventional engine layout in which the engines were mounted on either side of the nose with only approximately 3.5 feet between the propeller tips. The engines were also canted slightly outward to further minimize the effects of asymmetric thrust during single-engine operations.

The company touted benefits beyond the engines’ 2,000-hour TBO and better parts availability. While the engines were rated at 310 hp each, a sales manager said in an industry presentation that they derated them “with a pencil” and that the full 350 hp was available if needed. The Twin Cat’s total fuel consumption was the same as that of the single-engine radial Ag Cat. They also claimed the new layout improved forward visibility, prop clearance, and spray dispersion. 

When the time came for flight testing, the team got to see whether the new design could deliver the performance that backed up predictions. While the Twin Cat’s empty weight was the same as the Ag Cat’s, at 3,500 pounds, the maximum takeoff weight was 2,000 pounds higher, at 6,500 pounds. A load jettison function enabled the pilot to dump 2,000 pounds of payload if needed.

The new engine layout worked. With both engines operating, the Twin Cat’s takeoff distances were approximately 20 percent shorter than the Ag Cat. Asymmetric thrust was so effectively minimized that a sales manager claimed the Twin Cat could even take off with one engine shut down and then climb at 400 feet per minute at sea level. The company marketed this feature as a useful solution to ferry an aircraft with an inoperative engine to a location where maintenance could be performed.

In the air, the maximum cruising speed was 130 knots. By canting the engines slightly downward, the stall speed was remarkably low, at a claimed 49 knots for power-off stalls and 43 knots for power-on. A brochure claimed that the Twin Cat had “no V_MC,” which would have enabled flight all the way down to stall speed without controllability concerns. 

One account of the airplane’s flight characteristics suggests that it needed more refinement, however. It reportedly lacked any kind of rudder trim, and with an engine shut down, a pilot claimed he ran out of rudder and had to reduce power on the good engine to maintain control. It’s unclear whether the company planned to introduce rudder trim in future aircraft.

In the end, only three examples of the Twin Cat were rumored to have been completed and flown, and few photographs exist. One reportedly crashed, and the others presumably returned to their original single-engine configuration when the company decided against pursuing the concept any further. 

The post The One, Brief Life of the Twin Cat appeared first on FLYING Magazine.

Today’s Top Pick is a 1980 North American Sabreliner.

North American developed the Sabreliner business jet during the mid-1950s and first flew its prototype in 1958. The company also built military versions called T-39s in response to a request from the Air Force for jet utility and trainer designs. Like some early Dassault Falcon jets, the Sabreliner has the sleek look of a fighter. Indeed, the swept-wing aircraft’s name reflects its family resemblance to the F-86 Sabre that rose to fame during the Korean War.

North American and later Rockwell International built several hundred Sabreliners in many versions through the end of production in 1981. The jet for sale here is a 60 series model, which has a longer fuselage with more cabin space than the original design.

This 1980 Sabreliner has 11,470 hours on the airframe, 7,642 cycles since new, and 1,031 hours since the last major periodic service on engine 1, and 7,589 cycles and 165 hours since major periodic on engine 2.

The panel includes a Garmin GTN 750 Xi, Collins FD109 integrated flight system, Primus 400 radar, Collins APS 80 autopilot, dual Collins nav/comms, flight directors and DMEs Fairchild GA100 cockpit voice recorder, Collins ADF, and Skywatch TCAS.   

Customers looking for a high-performance business aircraft designed to cover long distances quickly with a combination of mid-century flair and military precision should consider this 1980 North American Sabreliner, which is available for $500,000 on AircraftForSale.

You can arrange financing of the aircraft through FLYING Finance. For more information, email info@flyingfinance.com.

• FLYING Magazine: History of Rockwell Collins’ Sabreliner
• FLYING Magazine: Getting Upset in a Bizjet
• Plane & Pilot: Rockwell 75A Sabre
• Plane & Pilot: Plane Facts: Bizjets
• AVweb: Retired Sabreliner Lives On

The post This 1980 North American Sabreliner Is a Fast, Stylish ‘AircraftForSale’ Top Pick appeared first on FLYING Magazine.

With a widening war, the strategic, fast, high-flying bomber project stalled in the 1960s, while the B-52—which excelled in a low-altitude role—remained relevant on bombing missions in Vietnam.

However, defense experts remained concerned about more advanced Soviet radar and surface-to-air missiles, making low altitude penetration missions riskier. Therefore, the USAF picked up again the task of creating a supersonic bomber to replace the aged B-52.

Under President Richard Nixon, Secretary of Defense Melvin Laird authorized the B-1A project in April 1969. A B-1A prototype built by Rockwell International completed its first test flight on December 23, 1974. Four prototypes of the long-range, high speed—flying in excess of Mach 2 at high altitude and Mach 1.2 at low altitude—strategic bomber were developed and tested. 

Unfortunately, the estimated unit cost for the B-1A increased from $40 million in 1970 to $100 million by 1977. Additionally, short-range cruise missiles had been developed that could be launched from B-52s. President Jimmy Carter canceled the B-1A program on June 30, 1977, before production began to reduce the defense budget. However, flight testing of the prototypes continued through 1981.

Production

Once again, a change in presidential administrations saved the B-1. President Ronald Reagan approved an improved variant, the B-1B, in October 1981. He wanted to push the Soviet Union to its financial limits, and a new strategic bomber would cause the Soviets to reinforce their air defense network. “Reagan bolstered the U.S. military might to ruin the Soviet economy, and he achieved his goal,” said Gennady Gerasimov, the top spokesman for the Soviet Foreign Ministry during the 1980s. 

The B-1B was slower and less expensive than the B-1A. According to the USAF website, among the key changes were “an additional structure to increase payload by 74,000 pounds, an improved radar and reduction of the radar cross-section by an order of magnitude. The changes led to a reduction in maximum speed to Mach 1.2.”

As modified, the B-1B Lancer was built for “high-speed, low-altitude penetration missions,” according to the USAF, which ordered 100 B-1Bs in 1982. A B-1B took flight on October 18, 1984, and flew at 60,000 feet with a range of more than 7,000 miles. The first B-1B was delivered to Dyess Air Force Base (KDYS) in Texas in June 1985, achieving initial operational capability on October 1, 1986. The final B-1B was delivered May 2, 1988.

Features

The USAF B-1B fact sheet states the “B-1B’s blended wing/body configuration, variable-geometry wings and turbofan afterburning engines combine to provide long range, maneuverability and high speed while enhancing survivability. Forward wing settings are used for takeoff, landings, air refueling and in some high-altitude weapons employment scenarios. Aft wing sweep settings—the main combat configuration—are typically used during high subsonic and supersonic flight, enhancing the B-1B’s maneuverability in the low- and high-altitude regimes. The B-1B’s speed and superior handling characteristics allow it to seamlessly integrate in mixed force packages. These capabilities, when combined with its substantial payload, excellent radar targeting system, long loiter time and survivability, make the B-1B a key element of any joint/composite strike force.”

During its first decade, the B-1B was primarily a nuclear deterrence bomber, serving as the third leg of the U.S. nuclear triad. While the B-1B Lancer was designed originally as a strategic nuclear bomber capable of flying swiftly at low altitudes to avoid Soviet early warning radars, the end of the Cold War and the collapse of the Soviet Union changed its mission beginning in 1994. 

The USAF adapted the B-1B Lancer to carry conventional munitions; updates improved the aircraft’s ability to precision-deliver conventional munitions, including advanced targeting electronics, and additional fixtures necessary to deliver a large number of bombs. “Since then [the B-1B] has been used extensively in close air support and tactical bombing missions,” according to Boeing, which acquired Rockwell International on August 1, 1996.

The conversion to conventional armaments began in November 2007 under the original START treaty and was completed in March 2011 under the second START treaty. 

Nearly 40 years after the first B-1B was produced, the aircraft remains “a highly versatile, multi-mission weapon system,” according to the USAF. For the next several years, the B-1B will lead the U.S. long-range bomber force and is capable of carrying the largest conventional payload of both guided and unguided weapons. 

According to Boeing, the B-1B “holds 61 world records for speed, payload, distance” and time of climb in its class. 

Combat Missions

During Operation Desert Shield in the 1990s, the U.S. military called almost every combat aircraft in its arsenal into action—it was the largest U.S. military mobilization since Vietnam. Similarly, during Operation Desert Storm, the USAF utilized the B-52 heavily. Because of its nuclear deterrence role, the B-1B was conspicuously absent during both operations—together known as the Gulf War. 

The B-1 saw its first use in combat to support the mission against Iraq during Operation Desert Fox in December 1998. B-1Bs penetrated Iraqi air defenses and destroyed Republican Guard barracks. This operation validated the conventional role of the aircraft and its ability to join in a force package. 

In March 1999, NATO forces began an air campaign against Serbia to end the human rights abuses against Kosovo’s ethnic Albanian population. Code-named Operation Allied Force, this effort ended 78 days later with the withdrawal of Serbian army and paramilitary forces from Kosovo. Six B-1s were used in the operation; they delivered more than 20 percent of the total ordnance while flying less than 2 percent of the combat sorties.

During the first six months of Operation Enduring Freedom (the war in Afghanistan and the global war on terrorism, which began on October 7, 2001, and lasted until December 31, 2014), eight B-1Bs dropped nearly 40 percent of the total tonnage delivered by coalition air forces. This included nearly 3,900 (67 percent of the total) joint direct attack munitions (JDAM), a guidance kit that converts unguided bombs into all-weather precision-guided munitions.

In Operation Iraqi Freedom, B-1B aircraft flew less than 1 percent of the combat missions while dropping 40 percent of the weapons and 70 percent of the precision-guided JDAM weapons.

During Operation Iraqi Freedom and Operation Enduring Freedom, B-1Bs were used in bombing, show of force, overwatch, and reconnaissance missions. In Afghanistan in 2007, B-1Bs also flew a search and rescue operation after Taliban forces shot down a NATO helicopter. B-1Bs flew 1,200 combat sorties, executed 3,000 tactical air requests, intervened in 432 ground engagements, and dropped 700 weapons during 2011. 

During the 2011 intervention in Libya, B-1Bs flew from Ellsworth Air Force Base (KRCA) in South Dakota to bomb Libyan targets—the first time B-1Bs flew a combat mission from the continental U.S.  

In Syria, B-1Bs were used against both ISIS and Syrian government targets. In April 2018, B-1Bs launched 19 JASSM cruise missiles because of the Assad regime’s chemical weapons attacks. This was the first use of the JASSM, which added to the B-1B’s already extended strike range. 

During these conflicts, the B-1B was used for precision bombing attacks, including close air support. Because of its range, it remained on station longer than the fighter-bombers used by the U.S. Air Force, Marine Corps, and Navy—although not as long as many drones.

The B-1B’s Future 

By early 2021, the 100 B-1Bs built by Rockwell in the 1980s had been reduced to 62 aircraft. The USAF retired about three dozen in the early 2000s and lost several others to accidents. Heavy use by the U.S. Central Command on close air support for ground troops in Iraq and Afghanistan—which the B-1 wasn’t built to do—took a toll. In 2017, the USAF reported that only half of the 62 bombers were combat-ready. In 2019, Air Force Global Strike Command (AFGSC) stated only seven were fully mission-capable.

In a September 24, 2021 article in Air & Space Forces magazine, the AFGSC stated it had “retired 17 B-1B bombers from its inventory, leaving a fleet of 45 aircraft,” which are located at Ellsworth AFB and Dyess AFB. 

The divestiture supported the USAF’s “efforts to modernize America’s bomber fleet” as authorized by Congress. The article stated a “smaller fleet will allow the remaining aircraft to receive more attention, spare parts, and generally achieve a higher level of readiness,” according to AFGSC’s director of logistics and engineering, Brig. Gen. Kenyon K. Bell. 

According to Bell, “The cost avoidance of operating the retired jets will also help pay for capability upgrades.” The Air Force indicated that “many of the aircraft had severe structural fatigue, especially at the wing-pivot points, because the jets were flying high and slow instead of low and fast with wings swept, as they were designed to do.” Bell also said, “The aircraft we retired would have taken between $10 million and $30 million per aircraft to get back to a status quo fleet in the short term until the B-21 comes online.” Most B-1B airframes will be at least 40 to 50 years old at retirement.

Several years ago, the USAF announced that the B-1B would be phased out over the next two decades. However, this plan was based on the successful development of the Northrop Grumman B-21 Raider, a dual-capable, stealth bomber. 

The USAF’s strategic plan is to use two bombers—the B-21 and the B-52H Stratofortress—the first of which came online in 1955. In an ironic twist, the B-1B will be taken out of service before the B-52—the airplane it was intended to replace. The USAF has not announced when it will retire another group of B-1Bs or begin retiring the B-2 Spirit fleet.

As noted in National Interest, significant delays in the B-21 program or “changes in the strategic situations” could cause the USAF to keep the B-1B flying, “much as the B-52 has remained in service well beyond a variety of projected retirement dates.” Whenever the last B-1B is retired, the U.S. “will no longer have a dedicated bomber capable of supersonic flight—but stealth replaced speed as the key metric of a bomber’s effectiveness some time ago.”

Legacy

When it was built, the B-1B was intended to deliver nuclear weapons inside the Soviet Union. Fortunately, the aircraft never undertook that mission.

Since then, B-1B bombers have served in multiple capacities, demonstrating a remarkable degree of mission flexibility. Although their numbers continue to dwindle, the B-1B is a key part of the USAF arsenal at this time.

FLYING Classics thanks Air & Space Forces Magazine, Boeing, military.com, the National Interest, OWLcation.com, and the United States Air Force for information and photos that contributed significantly to this article.  

The post <i>FLYING</i> Classics: B-1B’s Legacy of Mission Flexibility appeared first on FLYING Magazine.