Crystal Ball Gazing
It's probably useful to understand the background to the B757 purchase to understand some of the trade-offs and capability drivers.
The two converted Boeing’s were acquired as a direct replacement for the 727s in the strategic (passenger) transport role. The speed and range of an airliner were considered important because of the relative limitation of using the Hercules in these tasks, and because of the lack of Hercules capacity in the fleet size. The VIP role was very much a low cost adjunct function to the primary role.
At the time the Boeing purchase was made several other options were considered by Cabinet, including an all-Hercules fleet, a C-17 purchase, or converting second-hand aircraft.
The all Hercules fleet concept isn’t a new one, with a discussion paper in the early 1980s suggesting an 8 aircraft fleet for airlift, and a second set of 8 Hercules in the aerial refuelling role supporting the A4s. With a decision on Hercules replacement or upgrade being due around the same time as the expected end of life of the 727s, a contract option on 8 C-130Js was secured as a follow-on to the initial RAAF purchase.
When a recommendation was put to Cabinet, the range and speed limits of the Hercules fleet were causing planners some concern, and the preferred option of a direct replacement of the 727s with C-17s was put to government. The RAAF had recently adopted the C-17 and there were clear synergies in sharing intermediate and heavy maintenance, crew training, and both nations would benefit from a larger fleet size. A long way down the list was converting an existing airliner. The cargo door modification that was eventually settled on did mean the Boeings could carry standard military pallets (reflecting the changing relative importance of cargo versus passengers).
Having a airliner in the strategic transport role hasn’t alleviated the requirement to move bulk equipment by air beyond what a C-130 can practically accomplish. In an effort to extract more utility from the Boeings, an intensive care level aeromedical evac kit was built, and that’s now a role of the squadron as well.
That’s all history now, but what we can draw from it is that at least twice in recent memory the RNZAF has been prepared to trade-away the airliner ‘strategic’ transport in favour of a different fleet mix, and that some level of analysis has shown that if that fleet is C-130 based, then 8 aircraft are the preferred option (versus the current 5 Hercules and 2 Boeings).
The RNZAF is in the unusual position of being one of the few smaller Western air forces that has a true strategic lift requirement for its core operations. Routine destinations include Antartica (4000km), Darwin (5100km) and Singapore. Paradoxically most of the core operating area isn’t served by runways that can support heavy aircraft operations on any sustainable basis.
Airport facilities are particularly problematic for the Boeing, with only a handful of runways in the pacific islands having ground handling equipment to offload pallets. Operationally these means that if Boeing is needed for its capacity, a Hercules invariably needs to be dispatched with handling equipment as well. That leads us to the position that a reconfigured airlift fleet must be able to reliably perform strategic airlift of equipment and personnel, tactical transport and aeromedical evacuation. Ability to operate out of austere environments also features heavily, as does short runways.
With uncertainty around the eventual P-3K2 replacement, some capacity for search and rescue would also be sensible. That capacity being primarily the ability to airdrop MAD and other stores, some observer stations and ideally a electro-optical suite. All of that has utility for the tactical roles, and is inexpensive in the context of the overall acquisition costs.
Efficiency also comes into play. It clearly isn’t efficient to use a C-17 or A400 to move an infantry platoon from Ohakea to Christchurch. Similarly, using a C-130s to move an infantry company or a replacement helicopter engine to Singapore is slow and inefficient.
Commonality with like-minded nations is a thorny issue. We can look at the RNZN and RAN Anzac frigates and see platforms that started similarly, but ended up being quite different, just as we can with the P3s. Even the NH90s of both countries feature different engines and avionics options. In my view, that means a commitment is needed to either keep equipment as close to identical as possible, throughout the asset life, or to seek complimentary capabilities.
So that’ the theory. What does it mean in practice?
Option 1 – Like for like replacement. The Hercules are replaced one for one with another Hercules at the end of their service life. Probably the J model, but ultimately it doesn’t matter too much. It’s a low-risk, low-cost approach, but doesn’t do anything to increase capacity, and with the rise in weight of cargo types, the utility of the Hercules will continue to diminish over time. The Boeings get replaced at the end of their service life with something broadly equivalent. Type doesn’t especially matter. The odds of this option being chosen are at least even.
Option 2 – Single fleet type. Hercules and Boeings are progressively replaced with new Hercules, probably 8. Another low risk approach. Some flexibility is lost, but there are likely operational cost savings. The capacity for strategic airlift significantly diminishes. Not very likely.
Option 3 – A high/low mix. Boeings are replaced with C-17s, the 5 Hercules fleet probably reduced to 4. Low risk. Some increase in cost over Option 1, but offset opportunities with common support from Australia, and a significant increase in strategic airlift. Both aircraft sizes are over capacity for a good proportion of domestic tasks. Not very likely.
Option 4 – Another high/low mix (2). Boeings and Hercules are progressively replaced by A400s. 7 large aircraft are reduced to 5. Operational cost savings are likely. Transport capacity at any given range roughly doubles compared to C-130. Would require a small fleet of short-field, low-capacity aircraft to allow efficient operations. With no C-130 fleet, the advantages of the C-27 diminish. Casa 235 or 295 both contenders, with the C27 and Casa 235 being better for short fields. C-27 probably wins on a flexibility basis, but is likely the more expensive option. C-235 used by France in New Caledonia and the US Coast Guard.
What else is in the mix? If the P-8 is selected for the P3K-2 replacement, the requirements and opportunities change somewhat. The P-8 would introduce a 737 derivative into the fleet. Cost means that one for one replacement is almost certainly out of the question, and a reduction in MPA fleet size from 6 to 5 is likely, 4 not being out of the question. A modified P8, perhaps using a common airframe might be a low-cost way of retaining a jet transport aircraft and using the common skill base. It would be hard to rule out a like for like replacement of the C-130s and a P-8 airframe being used to replace the Boeings. Little change to transport fleet operating costs, no particular advantage, but some advantages in having attrition airframes available for the P-8 fleet (or the basis to expand the fleet in future).
Estimating costs is incredibly difficult to do reliably; the one obvious point is that the initial purchase price of any large transport aircraft (Hercules, A400 or C-17) is roughly the equivalent to purchasing some form of sealift asset. With Endeavour’s replacement likely to be optimised more for cargo than fuel, strategic transport capacity in the NZDF has significantly increased over the years, and there may be some appetite to keep looking at naval platforms. While the marginal operating costs are much higher, the capacity a third transport ship would give to the NZDF would be significant too.
My preference – It’s time to move past the Hercules. It’s done NZ great service, but the capacity constraints on the aircraft are becoming too much of an issue. Option 4 wins on a best-compromise basis. Fit a pair of both types with an electro optical turret, and have a pair of palletised mission kits for basic maritime search and rescue interchangeable between C-235 and A400. The prospect of competition for the MPA contract will drive down pricing on the P-8, and increases availability of the MPA for higher-end tasks. If the P-8 isn’t chosen, then either a C-235 or A400 derivative almost certainly will be, reducing support costs across the RNZAF. I’d also be inclined to add some transport capacity to the proposed Littoral Support Vessel in the form of a small vehicle deck, a 2-3 spot hangar and maybe a dozen ISO containers.