Crab; when I was at Manston and Wattisham, we had a procedure where we used to orbit at 1000ft, over the Channel, using the radop as an 'on scene controller', radar vectoring RNLI IRB's onto small vessels in trouble, when the vis made it impossible for us to see the surface at a 50ft hover.

Do you still do that?
I wonder if it's possible with a 120' weather radar?

IMC Let downs
 

Richard

The silence is deafening on the procedure using a 120 wouldn't you agree?

There's more.

When conducting an overwater radar search, ie using the radar to detect a missing vessel, I was always taught, correctly, to look downwind to minimise clutter. so you oriented yourself along the search box in such a way as to always be looking downwind. How's that going to work with a 120? Also, if the search is being conducted in bad weather in an area of high density moving contacts, how are are you going to maintain a plot of those contacts which you have investigated and cleared visually when you only have 1/3 of the picture. IR won't help much.

There has been a lot of talk about the SARH evaluation process with scenarios given for the bidders to solve. I know all about those but what I don't know and clearly what nobody is prepared to tell me is how solutions to these particular problems are achieved using the 120. Perhaps the IPT didn't think them very important or perhaps they were evaluated correctly but not considered important enough.

Cabe is right about one thing, the 120 is here to stay and we have to live with it but nobody has convinced me yet that the radar as fitted to the S92 will confer the same capability as that currently on the Sea King. Airknight bid with a 360 for this very reason.

Richard rightly points out that the Preferred Bidder is mandated to provide a service no less capable etc etc. On this issue, I can't see how Soteria can. Someone help me out.

Bertie - it's not an SOP but the big advantage of the dedicated Radop with all the sensors at his fingertips is exactly as you describe - he has an overview of the scene with the best SA of the crew and the ability to communicate with all the agencies directly whilst the pilots get on with flying and monitoring the aircraft systems.

Maybe it is others who are so dyed in the wool in their operations that they just can't cope with control over a SARop being exercised by anyone not in the cockpit;)

Iron

I've posed some specific questions about the relative merits of 120 vs a 360 radar. With all due respect I don't expect you as a maintainer to answer them but there has been a deafening silence from the operators of your shiney new service.

The 92 does have a good cabin I admit, whether that makes it a better platform for SAR is debatable but my questions are about the radar and from an operational perspective. Some 92 operator answer them please.

Yes the S92 is faster (although aren't some of the fleet limited to 130kts due to MRGB feet cracking?)

Yes the S-92 gets serviced less (if you ignore the 10 hour inspections for the MRGB feet cracking)

Yes the S-92 has a greater range (if you take up a load of the cabin space with the aux fuel tank).

Yes the S-92 has moving map displays (but who provides the obstruction database required to operate at low level overland at night?) Not AIDU who gives the military this capability I am pretty sure.

Yes the S-92 has a radar (but is it good enough to let down to a flooding estuary in fog to rescue stranded cocklepickers?).

Iron, I suggest you stick to maintaining and let those of us who do conduct SAROPs (Search and Rescue Operations - see that's not too difficult is it?) continue to ask pertinent questions about how the shiny new toys are going to be used in anger to perform rescue that are already within the capability of the current fleet. We should be expecting a step beyond current capability given the amount of money and technology involved - that is what moving forward to the future should give.

Rotary Girl:There must surely be someone on here with Portland S-61 SAR experience who can say how they've done it for all these years? I know they have had various IMC letdown procedures, including tail-first approaches in strong onshore winds, for some time, all of them by definition CAA-approved.
NS

North South,

There are many on here who await a response from anyone with experience of conducting IMC letdowns in strong onshore winds using a non-360 degree radar stating how it is done.

CD

aidu
 

Crab,

Fortunately, AIDU do supply all the low level mapping info that we require - 1:50k maps and the CHAD every 2 months. Sadly, we don't have a nice opsy to do the amendments for us :bored:

There is also a full digital CHAD/mapping service available from AIDU too, though that is not integrated at the moment.

On the subject of radar letdowns, I believe that full demonstrations were given to RAF specialist Radops to prove the required capability?

Calli

Calli
I would certainly hope that this is indeed the case.

However, can anyone comment on the ability of current (or future) civil SAR helicopters to train below SAlt whilst IMC utilizing internal radar for collision avoidance ?

Mmm ....

And what of the integration of I/R (viewer) technology into the Modern SAR machine as a complement to the RADAR?


:confused:

Iron - there are many threads where your engineering expertise is both relevant and valued but in a discussion about IMC letdowns you have nothing to offer except criticism of those who do want the discussion.

I asked the same question of the rotorheads community much earlier in the SARH process and the same deafening silence regarding SOPs and clearance to operate IMC below SAlt was experienced then.

Calli - it is exactly the integration of the digital service I am referring to - why isn't it already integrated on the S-92 and the 139? Do the crews routinely carry 50 thou cover of all the areas they might be required to operate? It makes a bit of a mockery of lauding the moving map technology if they do.

Calli,

If, as you say,'On the subject of radar letdowns, I believe that full demonstrations were given to RAF specialist Radops to prove the required capability?' is true then the question that I, and others, asked should be easy to answer.

Now that the preferred bidder has been announced, maybe the question can be answered by not only a civilian user of 120 degree radar but also one of the RAF specialist Radops that treated to a demonstration of the procedure.

CD

Here's my input on this:

How accurate is the nav system on the aircraft in question? If you have a nav system that is +/- 40ft, and a digital terrain map that is accurate to 50m, then you can derive a tolerance similar to the 75m radar clearance you've described with the legacy Sea King. Obviously, that does not account for non-terrain contacts. Once you through half pulse width inaccuracies into the radar mix, how accurate do you really need to be?
It should be obvious that a 360 radar with a dedicated operator is better than a 120 degree (what I'm used to) weather radar with a co-pilot, but does that mean the mission cannot be accomplished?

Bus driver

In answer to your last question, I'm afraid "safely-yes"

You can have all the map data in the world and a super swept up IR but you won't see surface contacts at night (boats etc) and /or in very bad weather without radar And in the UK environment sometimes you need the full 360 picture.

Clever

I think we are waiting in vain!!! and furthermore nobody has responded to my point on radar searches.

Perhaps I should be the one to stick his head above the parapet and say what
he really thinks, please feel free to join in if you agree.

The MCA have never been able to carry out full low level IMC overwater let downs or overwater searches in all the conditions described with the same degree of safety conferred by the Sea king and its 360 and to my knowledge they have also never had the Civil clearence to do it, partly because they have never had the radar to ensure that safety. Not in the 61, the 139 and now not in the 92 sadly. I know they do do it and it is a tribute to their determination, skill and downright ballsiness that they attempt it at all. I know there is an IMC overwater let down SOP but it isn't as comprehensive as the Mils because of their limited radar. But if the SARH contract were to hinge on this point and Soteria lost because they didn't have a 360 radar (like AK) it would be implicit that the MCA had been providing an inferior service (to the military) all these years and that would never happen.
I am prepared to admit on this forum that I am talking total horse poo if someone with experience of using the 120 radar in the UK SAR environment will describe how they would safely handle the 2 situations previously described (cliff let down - onshore wind and low level radar search) both at night and/or in bad weather.

Oh dear, now I've gone and done it :{

Lost Horizon,

I think you have stated exactly what a lot of people, including me, have thought for some time with regard to the 120 vs 360 degree radar debate. You have summed up the entire debate very eloquently and highlighted the deafening silence from some quarters when facts are requested as to the actual methods and procedures used.

I have no dog in this fight other than being an interested tax-payer with experience of the product delivered not matching the sales pitch in the context of Defence Acquisition.

CD

There have been quite a few comments stating that Airknight offered a 360 radar in their SAR-H solution compared with a 120 for Soteria's offering. Just out of interest, how do those commentators know? Do they all work for AK / Soteria / SAR-H PT? Just curious, given the confident tone of those posts.

Here's a thought: 120 degree radars are pretty standard for civilian aircraft, and I can't imagine that either integration or certification would be a problem. 360 degree radars, however, are certainly not standard in industry; not only are they significantly more expensive than a 120 radar, they are also rather more difficult to mount. This extra expense would be increased by any airframe design and mod work required, not to mention the time and cost of associated certification.

The bidders would have been required to meet a very wide range of requirements, but sadly there is only so much money in the pot to pay for the equipment to meet them all. Perhaps a 360 degree radar could have been provided, but only at the price of sacrificing equipment that would meet lots of other requirements. In the end I imagine the contractor decided on the most appropriate balance of equipment that was affordable, and a 360 degree radar simply wasn't. This isn't gospel, just my guess. For what it's worth I would have definitely preferred to see a 360 radar in the winning solution, but I'm a realist.

Serious question, though, as I'm genuinely interested in the answer: has anyone actually been in the situation where an IMC letdown and closure to the coast was required in an onshore wind strong enough to prevent a hover with a downwind component? In my experience winds of that strength have tended to clear the fog.

Louis

Louis - AK took a lot of rearcrew, including radop, input when formulating their solution whereas many of the Soteria personalities seem to be pilots. Additionally AK had a few very experienced, very recently ex-RAFSAR people advising them which may explain why they went for the 360 radar when Soteria didn't. It clearly can't have been that difficult or expensive an engineering solution to provide a 360 radar - it just depends on the will of the bidders. For CHC, as part of Soteria, it might have been too much of an admission to the charges lost horizon has made against them to have accepted that they haven't been doing things properly in the past, I don't know - maybe they really do believe they can achieve the same capability with a 120 radar (I and many others don't think they can). Time will tell unless the CAA are fobbed off with flannel.

Bus driver - only a radar (and a good one at that) will tell you what is actually there as opposed to what you believe is (or isn't) there, not GPS. The anemometer mast used to gather data for wind farm sites are a classic of something that will kill you if you fly into it but will not often be marked on the maps.

When I was a lad, flying SAR missions (amongst other things) in Mk 1 Sea Kings, locating targets ahead of the aircraft was a nightmare due to the 40 degree blind arc caused by mounting the radar behind the engines/transmission etc. It would appear that the radome is still in the same place, so how come we now have a "360 degree" radar?

QTG

You do blind arc turns and use the wind/drift combination to ensure that you only fly into areas that you have cleared. Simple!

Yes, that's what we used to do. So we don't have a 360 degree radar at all, and some of us seem to prefer a radar that doesn't see where we're going to one that does. Hmmmmmmmmmmmmmmmm