brar_w wrote:That new engine would be the 'Enhanced' which sees very little changes compared to the EDE but comes in with lower component life. I had a posted a summary of the EPE to EDE differences and the R&D portion was practically identical with very little in specific R&D that GE hasn't already done. What was earlier the EPE, had actual hardware differences compared to the USN funded work for the EDE, and those changes were never funded.
I don't think GE has any plans to actually begin offering yet another R&D program that looks at additional hardware changes to get higher thrust (compared to the EDE) without durability impact - that would naturally require additional spend at a time when they do not have $ commitment for the 4-5 years that it would take them to complete development testing of the enhanced engine changes they worked on for the USN. They are currently involved with 3 Next Generation propulsion programs that are likely to affect their military-engine business for at least the next 3-4 decades so I suspect that they would most likely wait and puruse the expected route if the USN funds it - i.e. deliver the changes the USN was interested in the last decade. That would get you the EDE.
What you are most likely to get is two thrust classes - 26,000 pounds with lower durability compared to the current baseline F414, or same thrust with much improved component life and therefore lower life-cycle cost and higher on times.
https://www.flightglobal.com/news/artic ... de-398210/
As things stand, GE offers the Enhanced Engine (Linked to the EDE) with 26,000 pounds of thrust. This would be your higher rated EDE.
http://www.geaviation.com/engines/docs/ ... hanced.pdf
Its of course entirely possible that someone can come in and spend the substantial amount required to complete development and get into testing but I would be skeptical of that since the USN's main headache is not lack of performance but lack of availability given physical depot capacity that will be a bottleneck for the Rhino fleet starting 2025 when large waves of aircraft would require SLAP. They are more likely to pursue a path that lowers LCC, and improves reliability.
I am looking for more info but there isn't much independent info - copies of a few same sources. From GE site - 2003:http://www.geaviation.com/press/military/military_2003616b.html
The EDE package includes a three-dimensional aerodynamic (3-D aero) high-pressure compressor, high-pressure turbine and exhaust frame, and lower-emissions combustor. The new compressor improves airflow and efficiency, and time between overhauls is increased from 4000 hours to 6000 hours. The 3-D aero turbine is more efficient, with higher temperature capability, while increasing fatigue life from 2000 hours to 6000 hours. These enhancements could be available for production F414 engines in 2009.
BTW @NRao - note that this link mentions possibility of F414 for LCA growth version - in 2003. Also do you know that RM12 was very seriously considered for LCA?? Volvo chickened out, due to GE pressure perhaps. Just a tidbit.
GE is also on an ambitious path to incorporate new designs and hardware to equip the F414 with increased thrust and improved durability. An F414 Enhanced Durability Engine (EDE) features both a new high-pressure turbine and new six-stage, high-pressure compressor to offer significant maintenance and fuel savings. The F414 Enhanced Performance Engine (EPE) will generate up to 20% more thrust by increasing fan airflow with the EDE hardware configuration.
Another more recent article 2015-16:
The F414 EDE is billed as an upgrade – not a new centreline engine – but it promises sig-niﬁcant performance improvement. The con-ﬁguration changes are exclusively hardware, but how the performance improvement is realised depends entirely on the software.
The navy can programme the full authority digital engine control system to upgrade the power output of the F414 EDE engine to around 26,400lb-thrust. The same changes can dramatically im-prove the engine’s durability if thrust output is maintained at the 22,000lb-thrust baseline
The trade-off with upgrading the engine to produce 26,400lb-thrust is a consid-erable hike in maintenance costs. Running the F414 EDE at the higher thrust setting reduces turbine life to 2,000h (comment - same as original F414), Caplan says. This is just one-third of the current 6,000h interval.
.In the end, the new passive cooling system integrated into the turbine blades was sufﬁcient to meet the requirements of the engine. GE conﬁrms that the F414 EDE turbine is equipped to survive despite a 66˚C (150˚F) increase in turbine inlet temperature.That increase in temperature margin is the key metric in achieving either increased durability of the overall engine at the baseline thrust level, or the higher-power, less-durable performance at higher thrust setting.
From above sources my assessment is:
So EDE = Vanilla F414 + Improved HPC (3D aero, 6stg) + Improved HPT (better cooling, increased TIT by ~60degC)
EPE = EDE + new fan (3 stage fan with all 3 blisk stages)
EDE HW changes improve Durability at same thrust - from 2000h to 6000h life for HPT. For HTP the main reason is improved cooling (+66deg more TIT limit) apart from small contribution from 3D Aero. Now EPE will bring down this life to 2000h for HPT again at ~20% thrust increase - due to increased TIT to new max limit. But this increase in thrust is also due to new fan i.e. increased Mass flow rate. Since we know the Thrust can be increased easily (at the expense of life) just by tweaking FADEC, GE can easily come up with a thrust setting where EDE uses the increased TIT limit to boost the thrust, even without new fan. Life will be same (F414 level) - thrust will be more - I am betting it would be around 10% - to ~110kN (Because the mass flow rate increase is ~10% which should give ~10% increase in thrust on its own account - linear variation of thrust with mass flow rate, rest 10% due to increased TIT). I have seen mentions of 110kN F414 version that India is interested in (some forums and reports such as one by Ajai Shukla, but they are not very reliable so not posting here - but if smoke is there, fire might as well exist somewhere, who knows). And I think GE can very well provide it with same life numbers as original F414.
Looks like down the line GE simply combined EDE and EPE in EE. Same engine will be giving both options - just choose thrust setting through FADEC. The currently open contract which was supposed to be signed last year but USG didn't provided for in its budget - for sure has all 3-stage blisk which means it has EPE changes.
But now it looks like even if India buys F414, it will be the EE version, and may be India will get to participate in new Fan design. GE would not share hot tech, but Fan can be done easily, as GE was anyway going to out source it.