This year’s Royal International Air Tattoo (RIAT) coincided with a major event for the G120TP programme, as Grob Aircraft’s highest-profile customer for the type so far cleared a key milestone on the path to training its first student pilots for the UK.
Three days before the gates were opened to the public at the 14-16 July show, the G120TP “Prefect” was granted military release to service approval for the Royal Air Force. The compact turboprop is one of three new types to enter use via the UK Military Flying Training System (MFTS) programme, with its introduction and support to be heralded by the Elbit Systems/KBR joint venture Affinity Flying Training Services.
Hot on the heels of the 11 July approval, Flight International was given the chance to try out the UK’s incoming elementary trainer at RAF Fairford in Gloucestershire, on the final arrivals day before RIAT.
Grob test pilot Tom Reinert brought the company’s first G120TP prototype – D-ETPX – to the show, while one of Affinity’s first of an eventual 23 examples for the RAF was on display in the static line, alongside a Beechcraft T-6C and an Embraer Phenom 100: the remaining elements of the fixed-wing MFTS fleet covered by its contract.
Royal Air Force students will fly elementary trainer from January 2018
Grob AIrcraft
After meeting on the north side of the airfield, Reinert gave me the choice of taking either the left- or right-hand seat of the side-by-side trainer. I opted for the right side, where a student getting to grips with flight in the early days of training would be positioned.
Entry to the aircraft was simple, requiring only a step on to the wing and another into the surprisingly spacious cockpit. With no ejection seats, a lightweight parachute was required, but this was simple to clip on and comfortable to wear. With no anti-g clothing to fit, and noise-cancelling headphones worn rather than helmets, our pre-flight preparations were swift.
With 107 aircraft scheduled to arrive at the RIAT site over the course of 13 July, our short taxi to Runway 27 required the services of a “Follow Me” vehicle. An extended wait before take-off followed, due to a low flypast and then landing of a pair of Ukrainian air force Sukhoi Su-27 fighters and an accompanying Ilyushin Il-76 transport. This gave Reinert the time to complete his final pre-flight checks and clear with air traffic control the favoured area for our short familiarisation flight.
It also provided the opportunity to capture a rare shot of an Su-27 positioned behind us, while we waited for the Il-76 to clear the runway.
Once cleared to depart, the G120TP was swiftly powering towards its 73kt (135km/h) rotation speed and climb-out at 90kt, needing only around 300m (984ft) of the almost 3,050m-long runway to leap to the air. We were operating at slightly below the type’s maximum take-off weight (MTOW) of 1,515kg (3,340lb), with less than its limit of 275kg of fuel.
After flying past the end of the show’s long row of static-display attractions, we made a sharp turn to the south, towards a waypoint at nearby Highworth, while climbing to 3,000ft from 116kt at a 15° angle.
POWER PLAY
We kept a training cruise speed of 135kt, with a torque setting (TQ) of 35%. Reinert also demonstrated the inherent power of the trainer’s Rolls-Royce M250 engine, by putting the aircraft into a maximum climb from only 78kt with a nose-high angle of around 25°, with the TQ rating briefly increased to maximum power. While a non-standard procedure that would not be employed during training, this illustrated the impressive power provided by the M250’s continuous output of 380shp (283kW), and maximum setting of 456shp, which is available for up to 5min. Grob Aircraft cites the aircraft’s normal maximum rate of climb at MTOW as being up to 3,000ft/min.
Familiarisation sortie was flown with German Company's first prototype from RAF Fairford
Affinity Flying Training Services
After showing some of the G120TP’s basic handling characteristics, and giving me the chance to control some basic turns, Reinert demonstrated its maximum speed of 238kt – reached swiftly at up to 100% TQ and a glide angle of only 3°. This is around 50kt faster than the G115E Tutor T1 that the Prefect will be replacing in RAF service. The increased performance is a welcome advance, including when performing longer sorties or repositioning flights, and the composite type can also be flown to a 25,000ft ceiling with oxygen supplies carried; versus 10,000ft for the Tutor.
We continued our sortie with aerobatics flown over Lambourn, Berkshire, including a loop, stall recoveries and a stall turn. Previously a Panavia Tornado pilot for the German air force, Reinert showed me some of the G120TP’s sharp performance, but only to 4g; comfortably shy of its 6g limit; the type can also achieve -4g. Handling was crisp and smooth, with rapid g onset demonstrated. Manoeuvres that would be used to prepare trainee commercial pilots in upset recovery were also demonstrated, by putting the aircraft into a nose-high attitude with rapidly dropping speed. Stall is achieved at 60kt with the gear deployed, with warnings including an audio alert and natural buffeting close to its onset. Pitch limit indicators are also shown on the cockpit displays. The Prefect’s R-R engine provides more than enough power to recover from such positions very rapidly.
In addition to showcasing the turboprop’s handling performance, our 40min flight also provided an opportunity for me to assess the experience that student pilots will have in the aircraft. The canopy provides very good visibility: particularly welcome given the high volume of traffic around the RIAT site that day.
I was also able to experience the enhancement that the type’s Genesys-supplied glass cockpit avionics bring, with the instructor and student each having one primary flight display and a multi-function display.
Affinity describes the Prefect’s role as “to teach ab initio students aviation principles and handling skills, as well as provide an introduction to basic navigation, night flying and instrument flying”. The digital cockpit layout represents a generational leap from the analogue dial-equipped Tutor, and will comfortably prepare new pilots for the digital cockpit operations they will later experience on the T-6C, BAE Systems Hawk T2 advanced jet trainer and frontline types.
The new cockpit is a particular area of satisfaction for Reinert, who was the lead pilot during its integration. Having also formerly been chief pilot on the G120A for the German air force at Phoenix Goodyear airport in Arizona for four years, this enabled him to address some of the earlier shortcomings of that model, to create an ideal training environment. Grob Aircraft also has developed its own simulator for the TP variant, and supplied this to all its existing customers for analogue and digital cockpit versions, apart from the UK.
Affinity managing director Iain Chalmers – a former qualified weapons instructor on the RAF’s Tornado GR4 – also recently got the chance to fly the Prefect after a decade away from the cockpit, and after just a 1h familiarisation session in a simulator. Noting that the G120TP has a “high-performance feel to it” while being “really simple to fly”, he says: “The instrument panels are very intuitive, and the visibility from the cockpit is excellent.”
Returning to Fairford via RAF Brize Norton control, we joined a busy pattern between an Israeli air force Lockheed Martin C-130J tactical transport and a vintage BAC Strikemaster. To enable us to clear the runway as swiftly as possible, Reinert performed a higher-speed run than would normally be used, after an approach and touch down at 80t and 70kt, respectively.
A new generation of the UK’s military pilots stands to benefit greatly from the G120TP’s introduction, with the first ab initio students to take to the air next January as the delivery of the next phase of its MFTS transformation will be fully put to the test.
For Grob Aircraft, the addition of a “marquee” operator for the G120TP – which is already in service with the air forces of Argentina, Indonesia, Jordan, Mexico and Myanmar, and also the US Army – should see interest climb to a new level. With more than 100 examples already handed over and further enhancements in the pipeline, the company is ready to deliver.
Source: FlightGlobal.com
