ASW Mission Management
I was looking at the original requirement for the Sea King, which is only about 20 pages long, and saw fully half of a page was for a “computer” to allow the pilot to manage the mission. Interestingly, the computer required didn’t exist yet, especially for relative plot (ie screening), tracking, and attacks. As for as I can tell it didn’t exist until the mid to late 70s ASN-123 (without proper radar integration), or the mid 80s TANS in the RN HAS Mk 5.
Interesting, it also wasn’t really needed at first because the RCN flew the aircraft like the USN. It was primarily an inner screen aircraft (the Tracker’s took the outer screen), and was under control of Bonnie’s Air Direction Center. As an aside, it’s quite impressive that the RCN did 24/7 ops keeping 4 Trackers and 2 Sea Kings plus an H-04S Pedro, airborne. The much larger Essex ASW conversions weren’t doing that.
A side note: the first three aircraft were delivered (directly from Sikorsky) without any ASW gear, as it wasn’t available. The remainder, built by United Aircraft of Canada, had the same basic fit as the USN SH-3A (ASA-13 “computer” and AQS-10 sonar). They also had some serious personnel problems getting the capability to sea (which they had told the government was extremely important to be done quickly). It feels like if you changed the date on some of the documentation to 50 years later and changed Sea King to Cyclone then it would be the same…
With the lose of the Bonnie and the Trackers at sea, there was a pivot (although doesn’t seem to be an explicit one) from the USN model to the RN model, of the helo being independent. It’s not clear whether the Sea King got a nav because everyone thought it was a great idea to have a crew like the RN, or there were extra ex-RCAF navs kicking around in, but got a nav they did.
However, they didn’t follow the RN in optimizing the back end for the nav’s presence. Instead they took surplus Tracker ASN-501s, which were designed for the Tracker role in the cockpit, and stuck an extra console in the back for the nav to use them. Thus was born the procedures for making the 501 go clunk to get the aircraft where it needed to be; the ASN-501 was never optimized for relative nav, dipping, or attacks (although it could have been).
This culminated in a series of mods in the 70s (right as the USN was introducing the ASN-123) which resulted in a radar, new sonar, and side facing console. The radar and sonar were tied to the ASN-501, but not optimized.
Things stayed that way, except for the advanced acoustic trials aircraft (14211, lost at sea), until the early 90s. During this time, the RN introduced the HAS(5), but there doesn’t seem to be any consideration that the avionics would be a better fit for Canada (the radar was integrated so better for close control). Two things happened in the early 90s:
Firstly, the Gulf War. Even though it was understood surface surveillance was important, the only thing that was done was to add a GPS. Although that meant your plot could be manually stabilized geographically, it didn’t increase the track count to what was required, nor did it integrate the radar. The number of tracks you could plot was limited by how fast the TACCO could make the ASN-501 go clunk.
Secondly, the introduction of HELTAS in 1992. It did have the USN ASN-123, not because of the need for rel vel screening or radar plotting, but because it was determined the ASN-501 could not handle the 8 LOFAR / 4 DIFAR plot. It wasn’t integrated to the radar in any way, nor was it optimized for a Nav.
In the late 90s it was decided that the entire fleet would be retrofitted with the ASN-123. This is in context of the USN determining that the 123 would be unsupportable after the early 2000s. Again, as seems to be a pattern, the 123 was installed without integration to the radar or sonar, and no “proper” way to conduct the bread and butter of Canadian Sea Kings until then, close fight dual helo tracking and attacking. It was again left to the nav to use procedures to work around the lack of integration and the pilot centric design, even while the ill fated EH-101 replacement was spec’d for something completely different.
Rev H-2(C) software in the early 2000s that the sonar and radar were (crudely) integrated, and some functionality to help with the close fight was added. Some of the functionality the USN enjoyed was never adopted. Notably, the way the USN dealt with the close fight with the co-pilot operating the computer, a ASN-123 specific datalink, was never adopted. Not only did that mean the entire plot could be shared between cockpits, but as well there were 123s in the carriers and frigates (for the SH-2S) so the ships could see what the helo had and pass situational awareness to them.
Meanwhile, the realization was made that the Gulf War wasn’t a one off, as MH saw a continuous string of deployments centered around low intensity surface surveillance, which even with the radar feed to the ASN-123 the back end wasn’t optimized for. The SCTF experiment also signaled the death of the HELTAS capability (which 10 years earlier had been considered a must have for transition to a new helicopter) when the 5 remaining CH-124Bs were converted to “troop carriers.”
There are a couple of side notes to the installation of the ASN-123, remembering that this was in the immediate aftermath of the cancellation of the EH-101 in 1993.
First, IMP did propose an “integrated mission system.” It was (probably for the best) not considered, as it wasn’t well defined and most likely vaporware.
Secondly, the ASN-150, a follow on to the 123, was available by then. It was installed in the SH-60F (the carrier borne replacement for the SH-3G). It retained the ASN-150 data transfer which was based on the 123 version, but was much more capable. Firstly, it had CDU (control data unit) for each of the crew members to do things like tune radios, etc. Secondly, it had two complete displays and keysets, one in the cockpit and one for the second aircrewman. Thirdly, it could overlay graphics and a single video feed. With a radar scan converter feeding the TACCO’s display it may have solved many of our surface plot woes.
However, we got the 123s surplus from the USN (some of them actually came from the LAPD who had bought surplus SH-3s and didn’t need ASW gear). They were cheap so that’s what we got.
The Sea King in the mid to late 2000s found itself doing a role it wasn’t optimized for low intensity surface surveillance), waiting for the Cyclone so not able to do any major mods, and without the transitional piece that HELTAS gave it.
What has always been missing, and was part of the replacement spec from the start, was proper integration of the radar. The separate tactical screen and radar screen makes it difficult to properly fuse the radar picture with the tactical plot. This hampers surface surveillance (and the number of tracks you can hold), and close ASW (because the sensor you use to coordinate with the other helo isn’t integrated with the tools you use to deliver the attacks).
As was stated previously, the USN overcame this by linking aircraft and ships together (not to be confused with Hawk Link, on the 60B). The RN had the capability from the 80s with TANS in the HAS(5), which integrated their (much better) radar with the tac plot and had an autotracker for two radar tracks. The Sea King needed either overlaid radar or an radar tracker.
It was decided to develop a low cost and low risk (airworthiness risk; the operational risk, that it might be worse, was accepted) solution for surface surveillance called Augmented Surface Plot (ASP). ASP digitized the radar and displayed it with the plot using off the shelf hardware and in-house software (the radar digitizer was actually a 4 channel USB oscilloscope). It also provided an “autotracker” in the form of AIS (Automatic Identification System). If there was an AIS track over the green radar blob, you didn’t track it with radar. Finally, there was an integrated camera to practice EO/IR plot fusion.
The ultimate purpose of ASP was to develop community knowledge on how an integrated system works by giving them something they could deploy with, as there were no resources to do something in Shearwater. Additionally, it would give the community practice in managing software. The appetite for ship’s to have an ASP equipped aircraft at times overwhelmed the Wing’s ability to learn from it, especially when TCDL (Tactical Common Data Link) was added, which gave the ability to pass the plot and imagery to the ship.
Unfortunately, the ASW interfaces weren’t allowed to be included. When it became obvious that the ASN-123 was to expensive to support, and ASP could do the ASW and SAR tasks, V4 ASP software allowed it to include those tasks and the ASN-123 was removed. The aircraft almost had the tools to do both surface surveillance and close ASW; what was still missing was the sonar interface, and an interface to the BDHI for aircraft direction (or even better, a display up front).
The final decision was to not continue with the next versions of ASP, due to the small screen, which would have added extra interfaces including the sonar and BDHI. Instead RCAF Project envisioned large screens for both the TACCO and AESOP, with a digitized sonar, and an MX-15. Although flight tested, this version died when the decision was made to push to the Cyclone regardless of whether it was ready.
The irony of how the tactical fit of the Sea King evolved is that even though a navigator was employed (the RN model), much of the capacity for command and control from that was eaten up by operating the equipment (which does not require an officer), so little capacity remained for command and control (which does).
Additionally, as time went on, the USN model evolved to remove much of the burden of operation by adding a dedicated helicopter link (eventually including a robust Link-16), better autotrackers, and better tools, so that the 60R actually has a decent capacity to operate independantly even though it doesn’t have a dedicated tactician (except in Australian et al service, where the second pilot is replaced by a nav). Ironically, meanwhile in the Cyclone the nav (ACSO) is still overcoming limitations in the radar auto-tracker and plot compilation.
This is what I meant by feeds into the current discussion in these forums. Hypothetically, if the Cyclone was to be replaced by the 60R (something I don’t support, I think we should put the money that was missing in the first place to solve the problems, even if Sikorsky can’t be convinced and we find somebody else, say IMP), who will occupy the left seat, a tactical pilot or a nav?
I lean towards a pilot; it allows the USN training system to be used, and allows robust OJT for the pilot’s. Junior pilots fly with seniour ones, and middlings fly together.
This also raises another question. Would it be better to offload the track and link management functions to a second AESOP in the Cyclone (it is a NCM function in the ship), remove sensor operation from the non-flying pilot (except possibly EO/IR as an extension of their Mk-1 eyeball and put in place better tools for that), and have the non-flying (pilot not in control) be the tactician, with an optimized toolset? Ie, no ACSO. This would give the master apprentice model in the back as well, and possibly streamline training?
Which raises another question; was the opportunity missed in the Sea King to explore this as the technology evolved?