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LZ4
3rd Jun 2011, 03:35
Hello!
Can anyone explain the procedure for a radar letdown in IMC in an offshore/coastal area used by SAR aircraft?


Regards,
LZ4.

3rd Jun 2011, 07:31
Start above SALT, clear the area you want to descend into using radar to detect obstructions/ships/cliffs etc, descend into cleared area using FCS/FPC/autopilot/SAR modes as required, close to target until visual or at minimum radar range.

Simples:ok:

krypton_john
3rd Jun 2011, 08:17
LZ4, I think the procedure is the same as on shore.

They start off by saying they want to stay friends....

LZ4
3rd Jun 2011, 17:17
Thanks for the info Crab.


How much separation would be maintained to obstacles/cliffs etc. during the letdown to the cleared area. How much sea room would be required for instance in a coastal area?

Is it possible for the approaches to the cleared area to be made out of wind in the Sea King?

Regards,
LZ4.

InTgreen
4th Jun 2011, 20:58
The RAF SARF generally work to 1/4 mile minimums on radar. As for the out of wind bit, the pilot can fly the attitude part of the letdown manually, thereby negating the kit limitations, but it is VERY advisable to be into wind just prior to achieving the hover. Training ideal is into wind with 50 kts on the clock if still IMC.:ok:

Tallsar
4th Jun 2011, 21:57
Intrigued to understand why you want to know this LZ4?:)

5th Jun 2011, 05:42
In terms of sea room, the trans down point from 200' is usually 1.25 nm downwind of the target point.

If you make a modified approach ie start the TD from downwind or crosswind and fly the turn manually to end up into wind then that distance can be reduced - it depends on the local geography, the direction of the wind and what obstacles there are; we do not overfly radar contacts in IMC below 1000 ft.

There is a whole other debate about what sort of radar you need to do this safely in all conditions but I won't start that again:)

pasptoo
5th Jun 2011, 10:22
Can anyone explain the procedure for a radar letdown in IMC in an offshore/coastal area used by SAR aircraft?

Pretty sure the boys n girls at Garda Cósta na hÉireann could help. Have you asked them?

2ndclasscitizen
5th Jun 2011, 13:23
To be on the safe side with an offshore wind, we usually advise to let down a little further away from shore (2nm at the bottom of the letdown), especially if there are cliffs or higher ground on or near the coastline. This is for two reasons, to allow yourself more space in case of an engine failure on the letdown. Secondly if the wind is up, to keep the aircraft away for turbulence in the lee of any high ground. At he base of the letdown you can always move in at 20kts reducing speed as you get closer to land. Theoretical minimum range for the Sea King radar is 78 yds but 150 yds is usually more realistic.

Hope this helps.

TorqueOfTheDevil
5th Jun 2011, 19:59
There is a whole other debate about what sort of radar you need to do this safely in all conditions


What sort is that, then?:E:oh:

LZ4
5th Jun 2011, 22:04
InTgreen & 2ndclasscitzen many thanks for the info!

Tallsar,
I'd heard of various SAR aircraft using the procedure and just had an interest about how it was carried out.

Pasptoo,
No, I haven't talked to them about it, was thinking some of them might be on here.Actually it would be interesting to hear another perspective on the procedure as well. The procedure used by CHC, for the Irish Coast Guard S-61 or HM Coastguard S-92.


Crab,
Thanks for the explanation and yes, that 330 versus 120 debate!


Regards,
LZ4.

LZ4
8th Jun 2011, 00:18
Now that I've heard the RAF Sea King procedure I'd be interested if anyone could explain the procedure for a radar letdown in IMC in an offshore/coastal area used by civilian SAR aircraft such as the S-61 or S-92?

How much separation would be maintained to obstacles/cliffs etc. during the letdown to the cleared area. How much sea room would be required for instance in a coastal area?
Is it possible for the approaches to the cleared area to be made out of wind?

Would like to hear it from a different perspective, using 120 degree radar.


Regards,
LZ4.

TorqueOfTheDevil
15th Jun 2011, 11:30
...or it's just not possible...360 deg radar = 3 times as good as 120 deg radar, just like everything else about mil SAR:E

Bertie Thruster
15th Jun 2011, 15:03
It had been a very long night. It was about midnight. We had already carried out a full 2 hour sortie in the SAR Wessex from Chivenor, looking for the source of a mysterious 'red flare' seen by several people from the North Devon coastline.

The coastguards had given us a large block of water to search, about 2 to 3 miles off shore. I was carefully following the Navs instuctions from the left hand seat as he monitored the search pattern using our ancient Decca machine dials and an almost incomprehensible map.

It was pitch black and at 500ft with no radalt hold or autopilot fitted, I was fully occupied with my instrument scan. The only person looking out was the third man of the crew, the winchman, sitting in the open doorway scanning with a pair of hand held NVG's. (The SAR Wessex was not fitted for NVG's and only the rear crew could use them to aid in searches)

Just as I announced we had only sufficient fuel for another 30 minutes of searching (and hoping we had probably been the victim of yet another 'FAWGI'
('false alarm with good intent') the winchman's incredulous voice called out on the intercomm; "Target sighted!"

"Two o clock, 1/4 of a mile, approximately, man in single seat dingy, waving"

What happened then was, on reflection, the crews first night 'drum winching circuit', conducted by the winchman on NVG's, the pilot on instuments and the Nav on adrenaline.

We found ourselves at a 30 ft hover (manual) with the casualty in the 2 o'clock at 10 units, (about 50 ft away).

Now in the Wessex, as the Nav has to climb vertically down into the cabin to take his position as winchop, the SOP was for this to be carried out (safely) at 500ft. The Nav sat with a set of dual controls in front of him. The 500ft was in case the Nav slipped on the rubber covered steps as he lifted his seat and gingerly extricated himself down into the cabin area. (Especially difficult if the Nav was slightly 'portly' around the tummy area.)

Our Nav tonight had the nickname 'Bear'.

He was not a slight man.


What to do? If we went up and around to 'safely' move the Nav at 500ft we would never get back to to this almost ideal position for picking up the casualty.

I made my decision and the crew agreed. The Nav unbuckled himself, stood up and pulled the seat up behind him. He took one step down the damp rubber waterproof indentations.

He then slipped down the rest of the steps until he came to rest, his movement arrested by the co-pilots cyclic firmly jammed between the inside of his lifejacket and his shapely body!

Shall I continue?

(Years later, I discovered Seaking night letdowns were like a breathe of fresh air!)

Aser
15th Jun 2011, 15:12
Shall I continue?

Please!

;)

SARowl
15th Jun 2011, 17:08
Civilian SAR aircraft have the ability to change direction whilst in flight. This enables them to fly a shortened circuit over the let down area to check for surface contacts and arrange the approach direction accordingly.

Mark on top (MOT) or Trans down to hover (TDH) will take you into the hover at the appropriate position.

The military guys would like you to think that it's a 'black art' that needs Navigators and 360 deg radars. It's mainly common sense...

Pip pip!

15th Jun 2011, 19:06
Sarowl - you must have gone to the same SAR school as the SARH winners - you know, the ones who didn't carry out a safety case analysis of the radar requirements for safe let downs in all conditions but still won the contract!

Saint Evil
15th Jun 2011, 19:15
Crab, can you just your bitching and sniping for 2 minutes.
None of the radars either Sea King or civsar/oil and gas are fully certified for what they are used for. The offshore safety case has been developed over many years and many letdowns. The CAA recently produced a paper about so the safety case is done elsewhere.

Having a different radar just means a different technique that's all. Doesn't mean less capable. If you want to get snotty about poor kit you should ground all of the mk3s for only having a simplex afcs.

Ttfn

SARowl
16th Jun 2011, 11:03
Also in civilian SAR the radar and FLIR picture is available to the PNF. Radar forward and FLIR pointing aft gives full 360 deg cover in the hover. In a Sea King, whilst winching, the radar/FLIR is unmanned leaving the Pilots in the dark. The Sea King has a blind arc straight in front - the worst place for it.

Cheers

Vie sans frontieres
16th Jun 2011, 12:30
Is that a special top of the range FLIR that can see through fog then? :rolleyes: Are you really on SAR, SARowl?

16th Jun 2011, 12:54
Goodness me, the annual cat check/line check for a PNF on the civsar fleet must be very extensive - as well as all the flying, navigating, RT, monitoring the PF and aircraft systems - he needs to be checked out on his radar letdowns and FLIR skills - he/she must be paid twice as much as the Captain for all that expertise.

A proper, independent safety case for radar letdowns, IMC overwater was conducted by one of the bidders for SARH - they then changed their spec from a 120 radar to a 360 one - why do you think that was?

Not saying the Sea King system is perfect - removing the blind arc would help a lot but it is much better to be able to see into an area where you are going to turn (not possible with a 120 without even more manoeuvring) and being able to stay heading into wind whilst you manoeuvre to radar minimums sideways or backwards makes for much safer operations.

PS the radar and FLIR screens are visible from the door when the Radop is winching:ok:

NRDK
16th Jun 2011, 17:42
Goodness me, the annual cat check/line check for a PNF on the civsar fleet must be very extensive - as well as all the flying, navigating, RT, monitoring the PF and aircraft systems - he needs to be checked out on his radar letdowns and FLIR skills - he/she must be paid twice as much as the Captain for all that expertise.

Normally the Capt does the highly paid bit and co-pilot flies/watches it do its automatics beautifully. But they (co-pilots) are more than able to do such 'mystical' feats of SAR God like tricks and are paid as much as a Crab SAR Captain for it.:}

A proper, independent safety case for radar letdowns, IMC overwater was conducted by one of the bidders for SARH - they then changed their spec from a 120 radar to a 360 one - why do you think that was?

Because their bid team was awash with Crabs as well and they hedged their bets, thats all....smoke and mirrors.:ok:

Not saying the Sea King system is perfect - removing the blind arc would help a lot but it is much better to be able to see into an area where you are going to turn (not possible with a 120 without even more manoeuvring) and being able to stay heading into wind whilst you manoeuvre to radar minimums sideways or backwards makes for much safer operations.

Well, you have convinced yourself so that's that matters. :ugh:

PS the radar and FLIR screens are visible from the door when the Radop is winching

Shouldn't he be looking at the winchman? hardly think squinting 45degrees across 5-6 feet in a poorly lit rear SK cabin at night is a sensible thinks whilst Biggles AFC & Bar is swing through the rigging below.:}:D

17th Jun 2011, 07:38
So, unlike a Radop who is extensively trained and checked to be able to accurately utilise the radar in difficult situations, the PNF just gets on with it and it's OK because the Captain (who also isn't a Radop) is watching him - that sounds like a very safe way of doing things, no wonder the CAA were so impressed:ugh:

How will the PNF with his 120 radar spot another vessel about to take you up the chuff in the dark/fog? I think the safety case looked at other situations rather than just the basic letdown and threat from ahead:ugh:

Lioncopter
17th Jun 2011, 16:38
Crab

In what situation do you see a vessel taking you up the chuff? I ask as im having a hard time thinking when this would be a issue...not to pick a fight.

Cheers

:)

NRDK
17th Jun 2011, 17:39
Like Lioncopter...

Me too?:ugh:

During the let-down in this magical black art of tweaking a radar to do a job:ok:. it is usual for one to note where various surface contacts are, (no we don't plot them blah blah) if it looks like we might get run over by a contact approaching where we want to be (stationary case) then we might just talk to someone about it:}

Once on the job with the rear crew unseated and working then yes we are now at the mercy of that mystery vessel taking us up the A@*#. But unless Biggles is still in his seat looking at your 330 degree radar then he too is in the door working and you too are the mercy of being bug#*%'@ from behind:O:*

Once the job is done we can see(radar) what’s directly ahead for our transition up without a nose turn like a Sea King:ok:

TAWS wise we have a 360 degree digital idea of where terrain is during this positioning let-down to supplement the radar and a moving map. ;)

Nuff said?? Who says the CAA has problems with it?? It’s been done for 25+ years and the kit is even better then then, same old crusty crews though, but hey we know jack sh1t and submit to your omnipotent like qualities.:hmm:

Wiretensioner
17th Jun 2011, 18:24
Yet again didn't take long to denigrate into another SAR bitchfest with all the usual suspects back on top form.

Wiretensioner (Ex)

18th Jun 2011, 06:17
How about a low level search for a MOB in a shipping lane?

Or just night training near busy shipping areas? This has been an issue and the day was saved by the Radop monitoring the radar from the door!

Or drum winching (grapnel for RN types) or night wets at night in a 5 kt tide going backwards to maintain station?

NRDK - so if you don't plot them how do you keep tabs on them? Ah yes the force Luke, that will keep your real-time picture updated - again a very safe SOP:ugh:

Once the job is done it is hardly a problem to yaw in the hover for a blind arc clearance. What do you do if there are obstacles ahead and you need to turn during the trans up??? I know, turn less than 60 degrees - whereas with the SK you can see all around (once blind arc clearance complete) and know EXACTLY where all the radar contacts/land masses are.

Is TAWS cleared for IMC letdown use? It does not use radar, just GPS and any plot slippage won't be evident. A moving map display is also GPS based and, over the sea, just gives you a big black space, cluttered with symbology - very useful.

NRDK
18th Jun 2011, 09:30
How about a low level search for a MOB in a shipping lane?

Or just night training near busy shipping areas? This has been an issue and the day was saved by the Radop monitoring the radar from the door!

Or drum winching (grapnel for RN types) or night wets at night in a 5 kt tide going backwards to maintain station?
Oh yes, AIS plot on the moving map. During this low level search for the MOB; how low are you for the FLIR operator? 200-300' feet should be just about right, and hopefully the FLIR operator notices the odd 80,000ton tanker too, just in case it got missed on radar.:ugh:


Once the job is done it is hardly a problem to yaw in the hover for a blind arc clearance. What do you do if there are obstacles ahead and you need to turn during the Trans up??? I know, turn less than 60 degrees - whereas with the SK you can see all around (once blind arc clearance complete) and know EXACTLY where all the radar contacts/land masses are.

Could the hundreds of civilian Offshore pilots answer this with their 120 degree radar please, I'm tired now.:ugh:

Is TAWS cleared for IMC let-down use? It does not use radar, just GPS and any plot slippage won't be evident. A moving map display is also GPS based and, over the sea, just gives you a big black space, cluttered with symbology - very useful.

Its another aid. Yep, the whole package, Radar/Flir/Taws/Moving map/AIS sh1t auto-pilot and excellent ex-mil backgrounds proven civ SAR experience & good sound SOP's sort the rest out. Not pissing Ex-Wiretensioner:hmm: just saying it gets done daily, year in & out by crews other than the light blue.

pasptoo
18th Jun 2011, 10:27
just saying it gets done daily, year in & out by crews other than the light blue

IMPOSSIBLE !

Only the RAF can do Search and Rescue. No one else is competent or safe enough to conduct such arduous missions. I do not believe that once someone leaves the military they would be able to do the same job when civilian - it's just impossible. Just like operating anything other than a Sea King in a SAR role. Wastelands should sell the Sea King to the Algerians instead of Merlins for SAR and not teach them with civilian crew either - they will not be able to teach military crews how to conduct SAROps.
:zzz:

My alarm has just woken me from the strangest dream.............:E

Quiz - How many RADOps/Navs/OBS become Pilots and why?
How many Winchmen become Pilots and why?
How many Pilots become Radops/Nav/OBS ?

Radar handling is not a black art and neither is piloting.

SAR makes use of many tools to achieve the end result. :E

Manchester
18th Jun 2011, 14:15
I think you miss the point ppt, its not all light blue crews that have the arrogant smugness of of a demigod, just one of them

19th Jun 2011, 06:27
Manchester - not a demigod, just someone who enjoys touching the raw nerves of those who are a bit too sensitive. The truth hurts, they say - maybe that's why there is such vociferous denial whenever I mention the radar issue - methinks the lady doth protest too much!

Tallsar
19th Jun 2011, 12:26
:D:D:D:D:D:D:D:ugh::)

NRDK
19th Jun 2011, 16:31
Well Crab, you tend to wind up your own colleagues more than anything. The rest of us love baiting the hook for you with some good old banter too. But seriously….

The original question was about SAR IMC let-downs…..

The RAF, RN & CG units all do it in their own ways and quite successfully.
Picture this for a moment though……you get transported to another part of the Country that’s not your familiar patch e.g. Western Scotland. Mission: a coastal type, plenty of Islands around etc. Night & Cloud down to 100-200’ or so, raining. Now as the RAF/RN front seat you have no idea up at MSA(IMC) where you actually are and what the ‘Big Picture’ looks like do you. Only what the Nav/Obs tells you, correct?

Now, the 2 front seat CG pilots have an exact model of situational awareness. With a moving map system, EGPWS Terrain Digital map, and 120 Degree radar that is more than good enough to clear the final approach path to the place they want to be. The FMS/Auto-pilot can handle all the transitioning whilst the 2 crew watch this picture unfolding. Not listening to 1 person telling them how it is. Remember the FLIR is of no use IMC.
Now as a pilot does that not sound like a great scenario?

Now you have a couple of seriously injured survivors on board and have to get back up. Fly to X airport via the ILS and the weather is really pants. You are sitting in the hover at night just below the cloud base, in the place your Rad/Obs placed you. The paramedic really needs the help keep these survivors medically stable. What do you do?

CG crew know where they are. Can get up (they can always get it up:E) to SALT, transit to a fully coupled ILS to a 50’ auto-level at the runway. All while the 2 rear crew are still doing first aid. Still sound good?

19th Jun 2011, 18:30
NRDK - as I said before, the Sea King system isn't perfect and a full 360 radar with a monitor screen in the front would be wonderful, but the fact remains that I would far rather trust my life to an expert radop who can concentrate 100% on the letdown with no distractions, in any conditions, anywhere in the world rather than rely on the cojo.

How often do your cojos actually practice radar letdowns? Pretty much every sortie for the Radops!

All the clever extras are nice but the only accurate assessment of how close you are to the coast/ship/target is a radar return.

NRDK
20th Jun 2011, 18:41
Crab – Not that you really read the scenarios and moved outside your 1980’s sandpit, your answer was bang on target in your usual way.:ok:

Well there you have it for those that asked about SAR IMC let-downs…..All scenarios aside, as long as 1 person can provide a talk down with his 330 degree Searchwater radar, that’s all you need for a safe let down. :ugh:

I wonder what your Ex-SAR colleagues that have had a go at the Non-RAF/RN way think about the equipment they have at their disposal. I think that with only 1 still left (LF)@EGPO perhaps an update from that person would enlighten you.:rolleyes:

20th Jun 2011, 19:15
Well Ok , if you want the specific scenarios then a map and the GPS/CDNU/RNAV gives as accurate a big picture as the symbology on a tv screen/MFD. Plus you have 2 people monitoring the nav - the copilot and the Radop - so you have a check and balance not available to the FMS equipped co pilot - how many times has a cojo misplotted the grid? When the Radop is monitoring you have instant confirmation or correction. It may not be 21st century but it works.

Scenario 2 - it is not the letdown itself that is the important part - even the Mk31 FCS on the Mk3 Sea King can do that bit - it is all the manoeuvring and clearing of that area (as ever it is all in the setup) where the Radop has the advantage with the 330 radar. Having flown the 139 with all the bells and whistles, it was only the FLIR that gave any useful SA during the letdowns at night, the EGPWS constantly bleats near land and the digital map shows a picture that is not real, just an electronic representation of the database and mostly black over the sea - however, being able to see the land/target dead ahead is a plus.

Scenario 3 - RAF/RN crew know where they are (map and GPS again) IF abort to above SALT and fly to airport for ILS the man's way - uncoupled (why we practise a lot I guess) but not to a 50' DH (your kit can do it but is it legal?) I thought the JAROPs 3 minima for ILS was 200'. Do you and the specific airport have CAT 2 or 3 autoland capability? Other than the transup the radop would be free to do all that messy medical stuff so no real difference there.

It occurs to me that if you are ex-RN, you are still thinking RN SKs where the Observer has the CDNU in the back - not so on Mk 3s and 3As where it is firmly where it needs to be - with the co-pilot - so plenty of SA available at all times.

Clever Richard
20th Jun 2011, 21:50
Back to the original question.

Can someone who has done an IMC letdown in strong on-shore wind conditions (ie where the wind speed precludes hovering downwind) using a 120-degree radar describe how they got on?

We will then be able to compare procedures (Crab has provided a detailed description of how he and his milSAR mates conduct it) and decide which is best for ourselves. Radical, I know, and not in the finest traditions of Pprune name calling.

Regards,

CD

Sven Sixtoo
21st Jun 2011, 08:55
In all fairness, it is necessary to consider the out-of-wind and hover performance limits of the various platforms when doing this type of analysis.

If the machine can hover crosswind at 45 kts and downwind at 30 it has a huge manoeuvre advantage over a SK, and the number of events where the approach capability is unavailable is very small indeed. Of course, the machine may well now be committed in the hover, or require an escape manoeuvre that's not practicable without near-360 radar, but SK is committed in the hover in a lot of other situations. Competing priorities, and that's why experienced crews with well-developed judgement are important.

Iain

Anyone need a SAR pilot?

Lost at Sea
22nd Jun 2011, 16:11
Crab,


Manchester - not a demigod, just someone who enjoys touching the raw nerves of those who are a bit too sensitive. The truth hurts, they say

Speaking of raw nerves Crab, how do you explain the private message you sent me a few years ago in which you referred to me as a 'complete ***'?

Methinks your nerves are a bit too sensitive too!!! :p

If you're going to dish it out you should be able to take it yourself instead of resorting to insults via private message.:=

Lost :E:E:E

PS Yes, I have been waiting years for this opportunity but it's always worthwhile pointing out your inconsistencies!:ok:

PSS How strange this debate has turned into your favourite argument. Is the original poster your Irish cousin??? :hmm:

25th Jun 2011, 10:19
Lost, I seem to recall the pm was as a result of some of the things you said about me on a public forum - I chose to keep my reply between us and I believe you fully warranted the epithet:ugh:

Night Watchman
26th Jun 2011, 12:35
Crab,

As you sit on top of ‘Brokedown Yellowcab’ Mountain looking down on your fellow pilots with contempt whilst pouring scorn on the rest of the aviation world who dare to fly aircraft without the RAF emblem emblazoned on the side, have you really ever considered that there is more than one way to achieve an tasking even if it isn’t written down in the RAF rule book?


I seem to recall that your argument for not having a dual hoist fit on the Sea King is that you have never needed a second hoist. (Actually, I think your argument is generally along the lines of - if it isn't in a Sea King then its rubbish.) My argument to you is that I have never needed a rearwards facing radar. There we go, we can all move on....:cool:


Personally I would prefer to have a radar that points in the direction the aircraft is going, that can be viewed by both pilots and even the winchop or winchman, rather than a radar that points backwards. It makes sense to me but clearly not to you. So be it.:)

Glad to see that you can be just as sensitive as everyone else on this site! It makes you seem a little bit more human.... that’s a good thing. We can start your rehabilitation back in to society now! ;)

NW

Clever Richard
28th Jun 2011, 17:03
Night Watchman,

I posted the following a few days ago:

'Back to the original question.

Can someone who has done an IMC letdown in strong on-shore wind conditions (ie where the wind speed precludes hovering downwind) using a 120-degree radar describe how they got on?

We will then be able to compare procedures (Crab has provided a detailed description of how he and his milSAR mates conduct it) and decide which is best for ourselves. Radical, I know, and not in the finest traditions of PPRuNe name calling.'

From your comments, you seem to have the experience required to answer my question. Although not stated explicitly, I did mean a 120 degree forward looking radar.

Many thanks in anticipation of a response.

CD

NRDK
28th Jun 2011, 19:36
Low level overwater ops--- you seem hung up on the 360 v 120 debate on this...what's your need to know pray tell?

If you are ex-mil then you will be familiar with an IMC let-down. If not, read crabs post. As for the 120 radar in civilian use, then just like the military, the approach is made at an offset angle (say 30-45 degrees) to the coast, accepting the crosswind. (Only a monkey in a gimp mask is going straight into the coast).

This gives a reduced 'escape' heading turn. When within a viable radar range, usually practised to .25nm and backed up by the FLIR operator if possible. Once visual it’s pedal into wind and winch-op con from there.

The current batch of 92/139 radars will hold a picture half as good again. Let’s face it if all the lights/Flir can’t make out anything from the .25nm point and in extremis beyond that then perhaps it is unlucky for those in need.
Wind above 40 kts I hear crab cry? you must back it in like the good ole boys do!

Well, easy as you go! It gets done, has been done and works at 33.3% of all the current UK SAR bases.

PS. For crab; most Civ Sar units have more Captains than the 'beloved co-jo's' you seem so incredulous about daring to do more than sit on their hands. So it is not a case of ye gad's they let co-jo's do radar talk-downs blah, blah.
Actually it is normal practise for the Captain to be managing the mission wth the co-pilot flying (70% of the time he is also a Captain!). The evolutions like these are practised by all the MCA SAR pilots, black art solved.:cool:

louisnewmark
29th Jun 2011, 14:29
... and backing in 'blind' from the 'first hover' position isn't a black art either, as long as you've previously mapped & checked the area with radar and are fairly sure that vessels which don't have AIS haven't cunningly sneaked in behind you while you weren't looking.

Even in the thickest fog you can see further than the edge of the rotor disc, so as long as you move at a steady, slow pace you are going to see the shoreline before you bump into it. Modern aircraft can control speed and direction of closing movement to a steady and accurate degree without suffering from the complications of old doppler-only systems, so the process is further de-risked. It's no different in principle to closing with the coast sideways or backwards (ideally not forwards unless committed!) below min radar range in a SK.

A good GPS display is also very useful for assisting awareness; if the system fails completely then you stop using it - but then the radar is just as susceptible to failure at an awkward moment. If the GPS is using RAIM then any error from one of the satellites being used will be flagged up as soon as the system recognises it, so claiming that the GPS position could be 'faulty' doesn't really hold water.

Both aircraft layouts and radar systems can achieve the same effect, just using different equipment combinations and therefore different procedures.

Just as well we don't get too many jobs at the back of coves in 40kts of onshore fog; think of the collision risk as the SK and AW139/S-92 operators race to prove how efficiently they can each complete the job!

;) Louis

Lioncopter
29th Jun 2011, 14:56
Louis : "Just as well we don't get too many jobs at the back of coves in 40kts of onshore fog; think of the collision risk as the SK and AW139/S-92 operators race to prove how efficiently they can each complete the job!"

Hehe... I have often had a giggle at the same thought!


One thing about the GPS in the s-92....we have 4 separate independent systems....part of the SAR checks is to make sure that the three easiest to read are all telling the same story. The forth could be used but it is by no means the easiest to access at important times....

jeffg
29th Jun 2011, 15:23
While I can't add to the SAR comments all I needed to know was summed up in these few words ...and fly to airport for ILS the man's way - uncoupled...

While some might have something to prove a professional is well past the point of proving himself "the man's way" and will use all of the tools available to include coupled modes because he knows it's safer. Doesn't matter if your talking SAR, military, EMS, corporate, those tools were developed and purchased for a reason. To not use them only speaks to ignorance or ego, both of which are bad things in a cockpit.

NRDK
29th Jun 2011, 17:11
Don't worry about that comment from Crab:ugh::ugh::ugh::ugh:

We have all been laughing on Pprune and in the crew rooms at that one.:ok:

Done it the mans way when it was all we had. Rather prefer the fully coupled spot on to auto-level at O'crack sparrow when shattered after that all night mission after a safe IMC let-down and cliff rescue:rolleyes:

louisnewmark
29th Jun 2011, 20:26
(Pssst...haven't you realised yet? I bet he's giggling to himself at your reactions!)

Crab: nicely slipped in there! :ok:

Louis