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Ando1Bar
9th Jul 2013, 22:32
A question for the ATCOs on pprune please.

Reading through an IFR book today it talks about 'surveillance radar approaches'. Basically, ATC provides track guidance down a final approach path if equipment failure has ruled out all other types of instrument approach. Is this still a back-up emergency procedure because I've never heard of it before and can't find it in the AIPs?

I believe it could also be called a cloud break procedure.

Oktas8
10th Jul 2013, 00:12
Not an ATCO, but have flown it (once!)

It is a non-precision approach like any other, but is ATC-interpreted rather than pilot-interpreted. Less work for the pilot, more for ATC. Mainly used when navaids are out of service.

Example (http://www.ead.eurocontrol.int/eadbasic/pamslight-4A70A3EC50FD16032883BF6FC79C55DD/7FE5QZZF3FXUS/EN/Charts/AD/AIRAC/EG_AD_2_EGHH_8-3_en_2011-02-10.pdf).

mates rates
10th Jul 2013, 02:43
We used to practice them at SYDNEY many years ago.Good practice for us and gave ATC recency.Imagine requesting one today!!

RAC/OPS
10th Jul 2013, 03:59
Still common in the UK. Used to give them on request for pilots, or request pilots do one for ATCO recency. UK AIP will have approach plates for them for the airports which provide them.

DeltaT
10th Jul 2013, 07:37
Cloud Break : This procedure is specified to enable aircraft to establish required visual reference for continuation of visual approach to the landing RWY. (and not necessarily lined up with the runway when at Missed Approach Point)
Depending on regs etc for the country, for NZ you can be up to 10nm from the runway.

Thanks to Wiki (http://en.wikipedia.org/wiki/Surveillance_radar_approach):
PAR: This is one in which a controller provides highly accurate navigational guidance in azimuth and elevation to a pilot.
SRA: This is one in which a controller, in ASR, provides navigational guidance in azimuth only

maui
10th Jul 2013, 07:38
Common in other parts of the world as well. Used to do them regularly in Korea at joint military/civil airports.

Basically it is a GCA without glideslope guidance, (azimuth only), runs down to non precision minima.

Maui

Arm out the window
10th Jul 2013, 10:24
Basically it is a GCA without glideslope guidance, (azimuth only), runs down to non precision minima.

Not quite right, I think, though I stand to be corrected. A proper GCA when they were around used a precision approach radar (eg the old Quad radar) with both glideslope and azimuth information allowing the final controller to get you down to ILS type minima as I recall.

The surveillance radar would vector you round into an appropriate position to be handed off to final, who would do the rest.

"You are dangerously below glidepath, I cannot control you further, look ahead and crash visually...!"

Centaurus
10th Jul 2013, 10:42
Many years ago, as an IFR flying instructor, I asked Melbourne ATC for a surveillance radar to 27 Melbourne. It was meant to be part of the students instrument rating training. Too busy, said ATC.

No problem so we tried the next day. Too busy, says ATC.

Third day I phoned ATC to give plenty of notice and asked what's the chance of just one lousy surveillance approach? Never happen, said ATC we are always too busy.

Arm out the window
10th Jul 2013, 21:32
When they got phased out of the military airfields I used to sometimes do my best to give them to the student over the intercom as a coordination exercise out in the training area. The 2 degree heading and 100 fpm ROD changes were great for developing a good scan.

Ando1Bar
10th Jul 2013, 21:59
Thanks for the feedback. So it's fair to say they are very rarely (never?) used in Australia anymore?

witwiw
11th Jul 2013, 00:20
Did them many years ago in India, pseudo ILS.

The controller spoke far more accurately than I could generally fly - "you are 5 feet below glideslope" or "you are 15 feet right of centreline".

A bit like a PRM nowadays, one freq selected to the GCA controller, monitoring the TWR on the other. GCA bloke cleared you to land.

Did one in anger to the minima when an ILS was U/S - worked a treat.

Great stuff, though, and as someone has mentioned, great for your scan rate.

Pity there's not more of it in Oz.

Clearedtoreenter
11th Jul 2013, 00:35
Thanks for the feedback. So it's fair to say they are very rarely (never?) used in Australia anymore?

Yes, that seems to be correct. They used to do them on request when I did initial instrument training in the UK maybe 30 years ago, at East Mids airport, which also had ILS and NDB approaches. I recall they weren't all that easy to do really accurately and needed currency. I think they used to talk us down to about 300'(?). I wouldn't dare ask for one here because they probably woundn't know what you are talking about. It would be good to have the option at somewhere like Bankstown, as an option if the NDB fell over and they could maybe be used to help out with some alternate requirements in many places. Often wondered why they don't do them here, where there are few ILSs and other options. They don't seem to offer them here even as emergency, which has often struck me as rather strange from a safety perspective.

Chief galah
11th Jul 2013, 09:54
Back in the 70's, Melbourne Approach used to do SRA's with the military out of Laverton.
The MIR3's would come up to Tullamarine on a "practise diversion" often incorporating a SRA.
Sort of training for both sides of the fence. One of these "practise diversions" undignifyingly ended up with a wheels up on Rwy 34 one day.
Reputed to be the only survivable wheels up by a MIR3.
I'm unsure if a SRA was involved with that, but the "practise diversions" seem to disappear from the repetoire after that, funnily enough.
The cloud break procedure is a different animal, basically (from memory - ouch)
involves radar vectoring into the circling area using the radar terrain clearance chart.
I think at the end of the procedure, 500ft lower than the radar chart
can be assigned in order to get visual. Not permitted at Melbourne to my
knowledge. Go figure. Happy to stand corrected on any of the above.

6317alan
11th Jul 2013, 13:30
Being on the last Nasho Aircrew intake in 1957 I had the opportunity to stand behind the pilot with a headset on and listen to 2 GCA let downs at East Sale in a Dakota one night after a trip from Laverton. Both let downs were to "round out, hold off, hold off, touchdown, touchdown, "Now"
Amazing how accurate both landing were!" Convinced Me!
I can remember being told it would never be adapted in Civi Street as the pilots would not hand that much control to someone on the ground!

Centaurus
11th Jul 2013, 13:52
They used to do them on request when I did initial instrument training in the UK maybe 30 years ago, at East Mids airport, which also had ILS and NDB approaches. I recall they weren't all that easy to do really accurately and needed currency

I vaguely recall that a 737-200 crashed during a SRA into East Midlands. It was a cargo operation and the aircraft got very low below the three degree slope with ATC reading out what height the aircraft should be at certain distance. eg Five miles - you should be at 1600 ft--turn left heading 272, four miles you should be at 1300 ft etc etc.

The aircraft was IMC and crew fatigued from multiple sectors. Anyway, the aircraft got so low it hit high tension towers and went in inverted.

fireflybob
11th Jul 2013, 13:58
Not ema but Coventry I believe! Fatigue may have been a factor? Nothing wrong with surveillance radar approaches so long as both atc and pilots current and practised!

Did many an SRA to RW 09 at ema in B737-200 in 1980s before ILS installed!

At many airports it was common before ILS and lower limits than NDB approach.

Rogan82
11th Jul 2013, 15:05
Have flown a few PRA's in to Butterworth, Malaysia in the last couple of years. A bizarre experience when you do one for the first time in IMC. Especially as there is no plate and therefore no minima written down. You just wait for ' don't reply, look ahead clear to land'. The controllers voice is unusually calming, almost hypnotic.

rick.shaw
11th Jul 2013, 17:22
How about some simple Google searches.

e.g. Surveillance radar approach - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Surveillance_radar_approach)

SRA's are similar in minima to VOR or ADF(what??) approaches. PRA's(or GCA's) take you down to Cat 1 minima usually. On military airfields in particular, GCA controllers can talk you almost touchdown if necessary(but under pilot responsibility). Their 'patter' after the usual minima is 'for info only'.

As a civvy from years back, I was lucky enough to have practiced a few with an ex RAAF instructor; usually to assist controllers maintain currency.

As an added bonus, I was invited to witness a GCI session(totally unrelated to this thread, but what the heck...). It was fascinating to watch with the controllers even knowing the pilot's voices and directing them accordingly on to their targets.

bam160
11th Jul 2013, 19:44
We still practice/use PARs/SRAs a lot here in Germany (military). Sometimes on controller's request because they have to talk down a certain amount of aircraft to keep current .
Depending on the controller they are either fun - or a stressful experience...

Yankee_Doodle_Floppy_Disk
22nd Aug 2013, 04:57
In NZ, PRA equipment was withdrawn many years ago and SRAs were written out of the manuals quite a while back now.

redsnail
22nd Aug 2013, 13:55
We do them reasonably often at RAF Northolt and it is possible to do them in Moscow however, our ops manual prohibits us from doing them with the Ruskies.

40years
23rd Aug 2013, 01:23
In the 70's and early 80's controllers practised SRA'S - sometimes live, sometimes on (primitive) simulation. A dedicated radar map was required, and if memory serves, ML had one for only one runway - RWY 16* (which is why Centaurus might have had trouble with 27). At one time there was a requirement on TMA endorsement and every year or so to demonstrate ability to conduct an SRA. Eventually the maps, techniques and practices were dropped, the reason possibly being that other modern aviation equipment and redundancy made SRA unnecessary.
*memory a bit dodgy here.

rubberprune
16th Apr 2015, 12:35
I found a video on how they work in the US. They actually shoot an ASR with an instructor talking the pilot (and the audience) through it.
If anyone has tried one recently in Australia or NZ, please let us know how similar they are. : )

https://www.youtube.com/watch?v=UCzvEZOR7t0

Ozdork
17th Apr 2015, 09:14
As was an operational Air Force.

QFF
17th Apr 2015, 10:36
I remember doing SRAs into the shorter RW28 at EGPF Glasgow in the late 1990s.

Landing into the setting sun (at 4pm in the winter!) might as well be IMC as you couldn't see the runway for the glare.

They used to be my favourite approaches as you let ATC do all the hard work in monitoring and calling out your approach - all you had to do was work the corrections...

Is one able to request one at YPPH these days? Would love to give the guys some practice there...:}

Capot
17th Apr 2015, 12:09
Just to correct an impression left by some, an SRA approach would be used with a surveillance radar providing horizontal position only.

In all the ones I ever flew or witnessed from the radar room, the pilot would be vectored to a point 6 miles from touchdown on the centre line, and advised to be at 2100 QFE, and to start a 3 degree descent at that point. The pilot had to know what that meant in fpm at the aircraft's approach speed.

From that point also the pilot would listen but not respond to the controller. Heading changes would be advised (eg right 10 degrees) as the controller struggled to keep the aircraft on the centreline in whatever wind was effective.

At each mile point the controller would advise the required height QFE and the pilot would correct the RoD as needed.

In my experience the guidance would be terminated at 2 miles, and if you were still in cloud you would break off and go away.

It is, however, a very long time since I did one!

What was a real challenge for a controller, and a test of accurate flying skill and nerve for a pilot, was the QGH approach, especially if, as a legendary ATCO at Sywell used to do, the controller was doing several at the same time.

baghdadkiwi
19th Apr 2015, 01:23
seems people are confusing cloud break procedure with PRA. Cloud break procedure was used a lot when I worked Ohakea sector (Military/Civil). Point the aircraft to the airfield and descended them according to radar terrain map and then within 10nm descended to 1500ft was authorised according to the 'book'. Was used as a way of getting aircraft on a visual approach. PRAs were discontinued many years ago and I don't believe any controllers in NZ would be current. PRA's were a controller talk down on equivalent of an ILS in todays terms. Cloud break procedure was from any direction.

TBM-Legend
19th Apr 2015, 04:00
Used to do them on HMAS Melbourne - called CCA [carrier controlled approach].

Controlled over 1500 GC/CCA's many in actual bad weather issues. Controlled a C-130 coming into Butterworth one Sunday morning from Bahrain...IMC with heavy rain and low cloud. All diversion airfields required an alternate; great satisfaction getting them on the ground in nearly zero vis in heavy tropical rain after three attempts. It got my attention when they said they would take a vector to the back of Penang Is and ditch as no more fuel to mess around or go anywhere. Talk down to touch down and a few Anchors afterwards!

Capn Bloggs
19th Apr 2015, 04:11
TBM-Legend, on behalf of my buddies, I apologise for doing those GCAs at 350KIAS and pressing the radio test button for the gear beep! :O

TBM-Legend
19th Apr 2015, 04:23
Fast jets were the easiest...a Huey coming to the hover on a GCA caught a few of the uninitiated off guard! The carrier approaches were fun as the ship only turned into wind late in the game so vectoring to a point in space which would hopefully be near finals...

Ascend Charlie
19th Apr 2015, 05:27
In the RAAF, the main reason for an SRA was to approach a different airfield from where the radar was situated, e.g.radar at Pearce, fly the approach to Gin Gin 15 miles north with the runway at 90 degrees to the radar. The controllers did a reasonable job, but they were dealing with students. And unlike the GCA where the radar sweeps painted the aircraft twice a second, they only saw the blip every 6 or 7 seconds, so the heading changes needed were considerably larger than on a GCA.

Chief Galah said, many years ago:
Sort of training for both sides of the fence. One of these "practise diversions" undignifyingly ended up with a wheels up on Rwy 34 one day.
Reputed to be the only survivable wheels up by a MIR3.
I'm unsure if a SRA was involved with that, but the "practise diversions" seem to disappear from the repetoire after that, funnily enough.

That wheels-up came from a short hop from RAAF Laverton to Melbourne, not a diversion. The weather was a bit ordinary and he wanted to stay VFR under the cloud, and he only had UHF radio, so I think he was talking to the tower via Mel Approach, as tower only had VHF at the time. At 250t plus it doesn't take long to cover the distance, and it was a straight-in approach, whereas the knuckleheads were only used to an initial/pitch/oval circuit to land. So, because there was no "downwind leg" he didn't do his "downwind checks" and screeched to a halt on his big drop tanks on the wet runway, the tanks being the only reason he survived - otherwise, the nose-high approach attitude would mean that when the tail hit the ground, the cockpit would slam onto the runway and drive the pilot's @ss into his helmet.

This was the cause of 2 things:
Changing the name to "Pre-landing checks"; and
The joke "How does a fighter pilot know he has done a wheels-up landing? He needs full afterburner to taxi."

Desert Duck
19th Apr 2015, 05:50
As a civvy in Darwin many years ago we were often asked if we would accept a GCA.
Fortunately our CP was ex military & we had a fantastic relationship with the controllers
Bloody great for IF skills & kept the controllers current - takes a bit of getting used to being told " 300 fpm NOT 250 fpm"