Editing Europrop TP400 (section)

==Development==

The TP400 was originally selected by [[Airbus Military]] to power the A400M in December 2000.<ref name="Interavia200012"/> However, [[Airbus]] reopened the engine competition in February 2002, because the engine core, which is based on the [[Snecma M88]] [[turbofan]] fighter engine, was too heavy and used too much fuel.<ref name="FI20020226"/> By May 2002, [[Pratt & Whitney Canada]] (P&WC) announced a proposal involving a {{cvt|12000|shp}} turboprop with a core based on its [[PW800]] turbofan,<ref name="AD20030508"/> a {{convert|12000|–|20000|lbf|kN kgf lbf|order=out|abbr=off|adj=mid}} regional jet engine under development that had a geared fan at the time;<ref name="FI20020506"/> the concept would later be called the PW180.<ref name="AD20030508"/> In 2003, around the 30 April decision deadline, Airbus Chief Executive [[Noel Forgeard]] told reporters that the P&WC proposal was 20 percent cheaper than for the TP400, and that he would have chosen to give the contract to P&WC, but government officials requested an extension for the companies to revise their bids. Before the final bids were modified, sources claimed that P&WC's offering, which had a European production percentage of 75 percent, was lower by USD$400 million.<ref name="WSJ20030507"/> On 6 May, amidst pressure from European political and business leaders, Airbus awarded a USD$3.4 billion contract to Europrop to produce 900 engines for the A400M, despite accusations of European protectionism.<ref name="GandM20030507"/> A member of Europrop claimed after the decision that the TP400 contract would only increase the costs of the USD$22.7 billion A400M program by about 1–2 percent compared to if the PW180 had been selected.<ref name="AD20030508"/>

[[File:Airbus_A400M_(39996402900).jpg|thumb|left|Two TP400 engines on the port wing of an Airbus A400M Atlas at the 2018 ILA Berlin Air Show. With the image zoomed in, the LH or RH markers become visible on the propeller blades, indicating that the blades are for the left-handed and right-handed propeller, respectively.]]

The signing of the A400M contract between [[Airbus Military]] and the European defense purchasing agency [[OCCAR]] on May 27, 2003 marked the beginning of the aircraft development program, which was planned to last 77 months ({{age in years and months |2003|5|27 |2009|10|27}}). At the 2003 [[Paris Air Show]], Europrop signed a 300 million euro contract with former engine consortium partner [[Avio Aero|Avio]] to supply the gearboxes. However, because of mechanical and aerodynamic problems that [[Lockheed Martin]] encountered on its [[C-130J Super Hercules]] upgrade, which used new engines and propellers that had half the planned output of the TP400, Airbus retained the option to select the engine configuration and the propeller for itself. The TP400 development schedule, which was considered very ambitious, had the bench run of the engine targeted for within 27 months ({{age in years and months |2003|5|27 |2005|08|27}}) of the contract signing, or August 2005. In spite of Europrop's insistence that testing on a specialized engine testbed aircraft was unnecessary, Airbus pushed for such a program on the [[Airbus A300]] or [[A340]] starting 11 months after the first ground tests. The engine testbed program would cost Airbus an estimated €40 million.<ref name="MilTech200307"/>

In July/August 2003, Airbus signed a contract worth up to USD$830 million with [[Ratier|Ratier-Figeac]] to supply the [[Propeller (aeronautics)|propellers]], which would be {{convert|17.5|ft|sigfig=3|abbr=off|sp=us|order=flip}} in diameter and have eight composite blades.<ref name="FRUpdate20030803"/> By May 2004, Airbus decided that the A400M design would have a "handed" propeller configuration, meaning that the pair of propellers on each wing would turn in opposite directions known as rotating "down between engines". Two different gearboxes are required, one with extra components to reverse the rotation of the propeller. This [[counter-rotating propeller]] design meant the TP400 engine would have to be certificated for two different gearbox/propeller configurations.<ref name="FI20040518"/> Airbus awarded [[Marshall Aerospace]] a contract in December 2004 to flight test the TP400 engine on a [[Lockheed C-130K Hercules]] aircraft,<ref name="AIN20100202"/> targeting flights in mid-2006 and hoping for a first flight in April of that year.<ref name="AW20041129"/> Other testbed airframes considered were the [[Ilyushin Il-76]] and what was thought to be the favorite, Airbus's own [[A340-300]] testbed aircraft, because, unlike the C-130, it could reach the A400M maximum cruise speed. The TP400 large propeller would still have enough ground clearance with the engine installed on the A340 low-mounted wing.<ref name="PowerStation"/>

[[File:A400M - RIAT 2013 (9360601998).jpg|thumb|A400M showing its [[counter-rotating propellers]] on each wing. A small difference in the propeller gearboxes is required to make them go in opposite directions, namely the addition of an idler gear in two of them.]]

According to the engine master program presented in September 2006, the TP400 was to reach its first engine run by the end of August 2005, followed by the first combined engine and propeller run by the end of that year. The TP400 would fly on its own specialized testbed aircraft by the end of 2006, and the engine would be certified with the "handed" propeller by the end of October 2007, 54 months ({{age in years and months |2003|4|30 |2007|10|31}}) into the engine program. The first test flight of the TP400-powered A400M would follow by the end of the next month, and engine certification with the baseline propeller would occur by the end of March 2008. Finally, the qualification test would finish by the end of January 2009.{{R|RAeS20060919|p=[https://www.fzt.haw-hamburg.de/pers/Scholz/dglr/hh/text_2006_09_19_RAeS_A400M.pdf#page=8 8]}}

After a two-month delay, the engine first ran on 28 October 2005<ref name="FlightGlobal20051107"/> using a [[dynamometer]] to absorb and measure the power developed by the engine. During subsequent testing, the engine reached full power.<ref name="FR200605"/> On 28 February 2006, the engine was tested for the first time with the propeller installed.<ref name="FI20060523"/> Europrop delivered the first TP400 engine for engine testbed flight testing on 19 November 2007.<ref name="FG20071123"/> In June 2008, the TP400 had a first ground run on the inboard port wing of the [[C-130]]K engine testbed, and integration was completed onto the first A400M production aircraft.<ref name="FlightGlobal20080623"/> After 24 hours of ground runs and taxi trials, the first flight of a single TP400-D6 engine took place on 17 December 2008. Airbus and Marshall completed [[flight testing]] on the C-130K testbed aircraft completed on 30 September 2009 after 18 flights, 55 flight hours, and 61 hours of ground tests, although the design of the C-130K airframe limited the maximum cruise speed to [[Mach number|Mach]] 0.64 instead of the TP400 propeller's Mach 0.72 maximum.<ref name="AIN20100202"/> On 18 November 2009, an A400M test aircraft completed a ground run for the first time with all four TP400 engines,<ref name="FG20091119"/> quickly followed by the A400M's first taxi trial on 23 November 2009.<ref name="FG20091124"/> On 11 December 2009, the [[maiden flight]] of the A400M took place.<ref name="Reuters20091211"/> The engine earned civil certification from the [[European Aviation Safety Agency]] (EASA) on 6 May 2011.<ref name="FlightGlobal20110531"/> By April 2012, EASA certified Ratier-Figeac's FH385/FH386 propellers for the TP400,<ref name="HB20120406"/> and on 13 March 2013 it granted a type certificate for the A400M aircraft.<ref name="AIN20130615"/> The aircraft and engine officially entered service on 30 September 2013 with the French Air Force.<ref name="AIN20131001"/>

Several technical problems delayed the engine's certification test program and pushed the entire A400M aircraft program into further scheduling adjustments. The engine delays were primarily due to problems with completing the [[full authority digital engine control]] (FADEC) software to the satisfaction of the civil authorities. More specifically, Europrop determined in mid-2008 that the engine worked correctly, but the FADEC software still did not meet EASA requirements.<ref name="AGB20090511"/> Since the A400M was intended for humanitarian missions, the aircraft also needed to have a civil certification. Europrop did not realize that this meant that every change made to the software in the FADEC had to be documented to enable [[traceability]] so EASA denied civil certification of the software. Because of this problem, the first A400M test aircraft, which was flight-ready by September 2008, was not permitted to fly. Europrop had to triple the size of its workforce to fix the issue,<ref name="EN20090508"/> resulting in a FADEC system consisting of over 275,000 lines of code, which was four times more complex than the FADEC software for the largest civil [[jet engine]].<ref name="Reuters20091212"/>

Further problems arose in 2016 with the propeller gearbox. It showed abnormal wear and inadequate management of the heat generated in the reduction gearing which required premature servicing.<ref name="Spiegel20160512"/> This problem led to the [[German Air Force]] temporarily grounding two of its three A400M aircraft, and also resulted in a [[Royal Air Force]] aircraft suffering an inflight engine shutdown.<ref name="Janes20160712"/> An interim fix for this engine issue was certified in July 2016.<ref name="Reuters20160709"/> The gearbox issues persisted, and as of July 2018, the final fix was planned to be introduced by the end of that year.<ref name="FT20180702"/>

[[File:Europrop Airbus A400M engine PAS 2013 03 TP400-D6 PDB Main Propeller Gearbox.jpg|thumb|left|The TP400 propeller gearbox on display at the 2013 Paris Air Show.]]