One of L 410 advantages is its reliability; however, as proven by experiences of many operators, if there is an occurrence of a technical problem, not allowing dispatch the aircraft, then a frequent cause is avionics problem. The history of L 410 avionics has been affected by origin of aircraft itself, as well as aftermarket history of the type.
L 410 was developed on a request of ex-soviet main operator Aeroflot. This fact affected a composition of avionics suite installed (OEM) into most of the units. As Soviet Union became ICAO member in 1970 (!), both ground and airborne navigation equipment, and practices, were developed in different environments to those as per ICAO Annexes. Legacy of this irregularity is still visible in many former Soviet Union states. The most preferred ground aid is still NDB and its airborne counterpart ADF. Instead of ILS, there is in use system called SP50, which works on different frequencies, but VOR/DME is available on international airports and routes only!
After L 410’s started to be delivered to ICAO countries, both new and aftermarket aircrafts, the question of a suitable western avionics was opened. Due to many reasons, most frequent suite are Bendix/King products, either Silver King or Gold King series. These units, and especially Silver King line, are suitably priced, but in fact, Bendix/King is only General Aviation avionics; in other words, this avionics is not designed for heavy everyday use!
In mid 80’ the development of “glass cockpit” solutions was launched by renowned avionics producers. First generation was using CRT’s, later on moving to LCD’s due to their less power consumption, higher reliability, better readability in sunlight etc.
Generally, glass cockpit display units have several advantages:
Higher reliability due to avoidance of mechanical extremely fine moving components
Versatility of displayed information in terms of contents and style of display leading to improved safety by decrease of crew workload
Possibility of copying between display units in case of a part of system failure, which contributes to improved safety as well
Only problem making glass cockpit not suitable for L 410 aircraft was price. So then L 410 operators, except some, still stay on mechanical instruments, and still facing problems as described above.
AEROSERVIS, s.r.o. is now developing a glass cockpit solution for L 410 UVP-E family. This avionics suite is based Genesys Aerosystems (ex-Chelton-Cobham) product IDU-450.
IDU 450 delivers:
Four LCD screens, two primary flight displays and two navigation/multifunctional displays with possibility of reversion display
Two integrated ADAHRS (air data and heading reference systems) with magnetic sensor units
Two WAAS GPS receivers
Features of the system are as follows:
Build-in TAWS Class A/EGPWS
EHSI/DME/ADF/ACAS II TA/EGPWS/moving map/3D terrain/WX radar display capability on MDF’s
Artificial horizon/ALT/RadALT/ASI/VSI including RA/heading/LOC/GS display on PFD’s
System is supplemented by:
Two GNC 255B NAV/COM’s
One DME KDM 706A
One WX radar control CP 466A
One ART 2000 WX radar sensor
One KRA 405B RadALT (unit only)
Back-up artificial horizon
Back-up CDI or RMI
Two audio boxes PS Engineering PAC 24 (direct KMA 24H replacement featuring LED backlight)
One KR 87 ADF
TPU 67B ACAS II, SW7.1 computer
One or two Mode S XPDRS (out of them minimally one MST 67A)
The major advantage of the glass cockpit equipped L 410 is less weight and lower maintenance costs caused by removing of:
AEROSERVIS Design Department is currently working on most complex project in its history: replacement of M601E engines on L 410 UVP-E and L 410 UVP-E20 by Pratt&Whitney Canada PT6A-42 engine
This is not first time, when PT6 engine is associated with the L 410 aircraft. In late sixties, when L 410 was developed and certified, the prototypes were powered by PT6A-27 engines, as well as first 38 serial production aircraft L 410A manufactured in early seventies.
The Pratt&Whitney Canada PT6 series engine is most famous and frequent example of small turboprop engine around the world, having excellent reputation in reliability, power, flexibility and operational support. In 2013 Pratt&Whitney Canada celebrated 50th anniversary of delivery the first PT6.
Because M601 engine was developed as direct replacement of PT6, while AEROSERVIS started to evaluate possible replacement, the PT6 was logical choice. There were several reasons to take decision to launch such a complex and expensive project. After taking-over the former Walter Engines by GE and forming GEAC, all costs related to operation of M601 engines start rising, customer approach by GEAC is not satisfactory, there still persist reliability issues from Walter times, while new appear (outer liner locks and related mandatory boroscopy, fuel control unit issues...). Compared to M601, the PT6 offers higher TBO, more flexible maintenance program, well developed maintenance and spare parts support worldwide.
The whole installation of new engine comprises:
PT6A-24 engine (flat-rated to 800 HP, i.e. max. contingency power of current M601E engine)
New all-aluminium five blade propeller Avia AV-725
300 Amps starter-generator (compared to original 200 Amps one) giving more electrical power available for next possible appliances installed (for example air-condition)
Replacement of several aircraft components
The installation is designed so to modify as much as possible existing components of original M601 equipped aircraft to save costs of installation.
The main benefits are:
Higher engine TBO: basic 3600 FH with possibility of individual TBO escalation, no cyclic and calendar TBO limits, and thus lower maintenance reserves for power plant
Lower fuel consumption
Increased cruise speed close to existing Vmo
Less aircraft noise both inside and outside due to lower prop RPM in both take-off and cruise
Improved “hot and high” performance
Because several original aircraft components with TBO/SL limits are replaced by new ones with no TBO/SL limit, simplifying the maintenance and lowering maintenance costs.
Milestones of project:
Autumn 2010: launching the project
October 2011: application to EASA for STC
Spring 2014: first engine run-up (planned)
Mid 2015: flight test campaign started (planned)
End 2015/start 2016: project finished, STC issued by EASA (planned)