Aviation Week & Space Technology
Andy Nativi
Casella, Italy
Putting the C27J through straight-and-narrow and downright show-stopping paces
Gimmick or gusto? What is the point of flying an airlifter at 60 deg. pitch-up and rolling 120 deg.? Air show bravado aside, the manufacturer is trying to demonstrate that the aircraft can operate beyond what will ever be tactically required.
Alenia Aeronautica has been doing its fair share of this kind of showmanship in recent months as the aircraft maker tries to persuade buyers in the Middle East, Asia and the Americas to purchase its C-27J.
Alenia chief test pilot Marco Venanzetti and test pilot Enrico Scarabotto took this Aviation Week & Space Technology editor on the type of flight usually reserved for potential clients.
In fact, the pair had just returned from Qatar and Oman, where they were helping to hawk the tactical transport in the severe 46C heat. There, they also air dropped different types of cargo, and conducted load trials with an up-armored Humvee outfitted with a roof-mounted machine gun.
Alenia Aeronautica has begun demonstrating performance from sand airstrips to drum up interest from customers in the Middle East.Credit: ALENIA AERONAUTICA PHOTOS
Some of the operations took place on bare sand airstrips, which presented a new challenge for the C-27. “One of the advantages of [this type of] landing is that you lose speed pretty quickly because the landing gear sinks into the sand, and this shortens the landing run,” Scarabotto says. On the other hand, “to avoid a total, albeit temporary, brownout you need to be careful when using reverse power,” he adds, describing the technique to avoid the aircraft being entirely enveloped by sand and hampering a pilot’s vision.
By comparison, our operations from the tarmac at Alenia’s Caselle facility are considered to be a breeze. The aircraft fuel load was limited to 3,000 lb., bringing total take-off weight to 44,452 lb., the standard “light” set-up for demonstration flights. Our aircraft features some nice options such as autothrottle and a moving map display. We fly without head-up displays, airborne air refueling probe or a defensive aid subsystem, which are standard in the Italian Air Force configuration. I experience a momentary qualm when the pilots quip that the HUD would be merely in the way with the types of maneuvers that they have planned.
With me strapped firmly into the third cockpit seat, the crew starts the auxiliary power unit and then the two Rolls-Royce AE2100 turboprop engines. In addition to a quick check of controls (this was the second flight of the day), the crew review the special checks for the acrobatic flight.
After releasing the brakes, Scarabotto uses the left-side wall-mounted tiller to steer the nose wheel during taxiing. The C-27J features dual ground idle modes for the engines, either at 75% or 99% power, depending on the aircraft weight. Aligned on Runway 36, we are cleared for takeoff.
The aircraft jumps on the struts and quickly accelerates. Scarabotto, who has logged more than 3,500 flying hours, including 1,500 on multi-engine aircraft, is the pilot in command in the left seat, while Venanzetti, who has logged 4,000 flying hours, mainly on fast jets, takes the right seat. Each man is qualified for either seat position to ensure full crew coordination and awareness of duties. With flaps in No. 1 position and 0.5 deg. of nose-down trim, the aircraft reaches V1 at 93 kt. and lifts off at 115 kt., with pitch increasing to 30 deg. for a steep climb.
We establish cruise at 240 kt. and 3,000 ft. altitude, and head to nearby Levaldigi airport, a mere 36 mi. away, to perform the display routine. Venanzetti explains that we will use the Romeo 64 military space, an area the company routinely uses for testing because it can extend up to 40,000 ft. to allow supersonic flights over the North Tirrenian sea.
It just takes a few minutes to reach Levaldigi. Slowing and descending, the crew perform a steep landing. Scarabotto points out that in many tactical conditions, a steep approach is preferable to reduce exposure to potential threats—this is particularly pertinent now that aircraft are increasingly coming under ground fire around airports. Furthermore, the technique allows short landings even at high approach speed. With a 94-kt. approach speed at 1,000 ft., the pilots command a 15-deg. nose-up attitude to lower speed slightly, then push the yoke to reach a 30-deg. dive. The engines are set at idle with the steep descent throttle position engaged. Under this mode, idle torque is reduced to a minimum and propeller pitch is adjusted to deliver negative thrust.
The C-27J quickly builds up speed to 130 kt. indicated air speed, the dive reaches 40 deg., and the aircraft touches down at 110 KIAS. Regular operations, which would come with a shorter landing distance but expose the aircraft to more ground fire, would see the aircraft land at 90 KIAS.
Current rules limit the C-27J to around 10 sec. of inverted flight, making a loop possible.
By applying maximum reverse thrust and full brakes, the aircraft can stop 300-400 meters (984-1,312 ft.) from touchdown, although that maneuver would not be performed since more flying lay ahead and we didn’t want to overtax the brakes. Even at heavy weights, the C-27J can handle short runways. For instance, at 27,000 kg. (59,524 lb.) total weight, it needs a landing distance of 320 meters. Performance on takeoff isn’t as sporty, but a C-27J weighing 28,000 kg. needs only 609 meters of runway.
And now the real flying begins. The aircraft is quickly aligned along Runway 03 and the crew undergo checks and properly configure the aircraft, turning off the ground collision avoidance system, setting the barometer to the altitude limits and tightly strapping in. For the kind of acrobatics that are going to be performed, a G-loads indicator is added to the top left instrument panel, otherwise we rely on the standard five 6 X-8-in. displays. The G loads can be read on the primary flight display, but the extra additional indicator is to enhance situational awareness.
For safety reasons, the hard deck for the display is set at 304 meters, against the standard 152 meters used for air shows. This does not particularly affect the crew’s work load.
We commence with a steep takeoff, which requires a higher speed of 115 KIAS to build up energy. Pitch attitude is around 40 deg. and the flaps, initially set in the 50% down position, are gradually raised. Then, a deep descent is commanded to enter the second maneuver, a spiral turn, which requires the aircraft to accelerate to 150 kt. at full power. We follow that with a shallow climb, during which full left rudder is applied to obtain a 180-deg. course change.
At this point, G-forces are evident, and the feel of the tightly locked seatbelts is reassuring as the large tail appears to disappear and the aircraft almost snap-turns. The C-27J’s significant rudder power and no yaw limitations allow it to easily reach 20 deg. beta.
As the Spartan reaches 457 meters, speed decreases to 90-100 KIAS at which point we level out before entering a series of three wingovers. Again at full power and at a high 220 KIAS entry speed, the pilots pull back the yoke and the pitch increases quickly to a maximum of about 60 deg. at the apex, while the aircraft is also rolled to 120-130 deg. The aircraft tops out at an altitude of 1,066 meters, while speed drops to 110 KIAS.
Close crew coordination is essential and the pilots appreciate the wide field of view offered by the 16 cockpit windows. Through them we can keep constant watch of the position of the display line and a terminal building we had earlier selected to serve as the grandstand and a reference point.
Following the last wingover, it is time to try a knife edge—probably the most complex maneuver for a tactical airlifter, demanding perfect synchronization of the actions of the two pilots. The aircraft is rolled and simultaneously is unloaded to -0.8/-1g at 180 KIAS. The pilots initially apply one-third right rudder, then full right rudder and left aileron to push the aircraft to more than a 90 deg. angle-of-bank. We go to 95-100 deg. to sustain some wing lift and the pilots also have to resort to the use of differential engine power to maintain the attitude.
The C-27J does not like the treatment, but remains stable in this unusual attitude, which can be kept for as long as 10 sec., before coordinated rudder and aileron are applied, again, to return to level flight.
Next on the agenda is a low-speed steep turn that ends in a reversal of direction. Entry speed is built up to 180 KIAS, then the aircraft rolls to more than 60 deg. of bank driving G-forces to 2.5. Speed drops to 130 KIAS, the landing gear is lowered, and flaps are lowered to the mid position. After completing a turn of almost 270 deg., we reverse direction twice in quick succession and prepare the Spartan for a demonstration of its short-field landing performance.
We perform the extreme takeoff-and-short-landing sequence as a steep pull-up, followed by pushover, arallel to the runway. With a speed of 150 KIAS, a 50-deg. pitch attitude is reached, then the C-27J is slowed to 120 KIAS and a massive pushover is commenced, to reach an idle descent attitude (with the engines retarded) with 40-deg. nose down. This is the most structurally demanding maneuver, with loads spanning from -1g at the pushover to the maximum 3g allowed.
Alenia test pilots are trying to perfect this very dynamic maneuver, nicknamed “zompo” (Italian slang for a jump), and perform it as a takeoff and landing within the length of the runway. That can be done, but convincing air show authorities to allow it is another matter because a small mistake can cause the aircraft to crash into the runway in a steep dive right in front of the grandstand.
Nearing the end of the demonstration, we perform a barrel roll—a somewhat unusual maneuver for an airlifter but a fairly straightforward undertaking with the C-27J. The nose is elevated to 20 deg., speed is 200 KIAS, then three-quarters-to-full aileron input is given and just a modest push to the yoke is applied to depress the nose and exit the barrel roll perfectly level. No rudder input is required. The C-27J accelerates in roll pretty fast and a steady 60-deg.-per-second roll rate is acquired. Exit speed is about 200 kt. and the aircraft gains almost 400 ft. of altitude. The maneuver takes less than 5 sec., well within the 10-sec. limit allowed for inverted flight.
At this point the exhausted crew (and editor) can recover with yet another tactical landing. After a few minutes cool- down, we are headed back to Caselle. On this leg, we spend some minutes at low level where I have the opportunity to take the controls and find them to be crisp and responsive. I perform a few tight turns, reaching instantaneous 3g. The engines react quickly to throttle inputs, thanks to the Fadec.
What’s readily apparent is how the responsiveness of the C-27 would allow pilots to quickly react to potential anti-aircraft threats, to maneuver with precision in tight spaces and to deal with other unforeseen events with relative ease.
Venanzetti also shows me the performance of the Northrop Grumman APN-241 radar, which is somewhat of a luxury for a transport aircraft of this class. It delivers solid Doppler-shift mapping mode functionality and has a good weather and beacon mode for search-and-rescue missions. There’s even some limited air-to-air capability to spot fighter aircraft at tactically relevant ranges.
We return to Caselle airport using the autopilot to fly a direct instrument landing system approach. Landing at a weight of 8,618 kg., we encounter a long taxi time due to civil traffic and finally reach the Alenia Aeronautica ramp for a shutdown. Total block-to-block time has been 55 min.
So what other maneuvers could be performed? I ask the pilots if they have considered a full loop. Some Italian air force experimental pilots have done just that with the C-27J’s predecessor, the G-222. Scarabotto replies that they’ve performed the maneuver, but only in the simulator, and it was a success even though the aircraft almost reached the maximum permitted 10-sec. inverted time.
But in real life, he notes, it’s not worth the time and effort, since it’s highly unlikely authorities at an event like Le Bourget or Farnborough would ever clear the maneuver.
