LKTB - Surveillance Radar Approach

Basic Information

What is SRA?

A Surveillance Radar Approach (SRA or ASR) is a type of instrument approach provided with active assistance from ATCo during the final approach phase. It requires no special equipment in addition to a standard surveillance radar system used by ATCo. Thus, it differs from most other instrument approaches which utilize a radio navigation system to provide guidance during the final approach.

As it requires no special equipment to be carried on board an aircraft, an SRA is considered a fall-back approach for aircraft that are having instrument or electrical problems and therefore cannot rely on on-board instruments; it is also sometimes provided to runways that do not usually receive instrument traffic and therefore do not have any other approach aids provided.

During the approach, the controller provides headings to keep the aircraft on the runway centerline as viewed on radar. The controller also reads out advisory altitudes based upon the observed range from touchdown: pilots can use these as assistance with their descent planning. Since only lateral guidance is provided, SRA is a non-precision approaches. The controller guidance terminates at between 2 NM and 0,5 NM from TDZ, at which point the pilot must either have visual reference, or must go around.

According to special ground equipment necessary for providing the service, SRA is used mainly as a reserve for emergency situation.

Since 10 February 2011, SRA is not any more used in the Czech Republic.

However, although this kind of approach was cancelled in the real world life, on VATSIM it is still published for Airport Brno - Tuřany, and SRA is used in case of special events..

SRA has no published step down fixes so descending to some certain altitude just after passing FAF is not possible (like when flying VOR/DME and other NPAs). After passing FAF the pilot should maintain constant descent rate and correct it according to altitude checks from ATC.

Further Information

What to expect at the beginning

While approaching the aerodrome, ATC gives you vectors near the RWY centerline and hands you off to the ATC position that provides SRA (SRA ATCo). SRA ATCo gives you all necessary information (RWY heading, angle of descend, OCA, MDA, terminal range and missed approach procedure). SRA ATCo also gives you vectors into intermediate approach track (onto RWY centerline, horizontal flight).

Check Your Minimums

SRA ATCo gives obstruct clearance altitude; however, pilot should have his/ her own minimums (same or higher then given by ATCo).

For example, EU based airlines use JAR-OPS (EU-OPS) document where the minimums are determined like this:

• SRA (terminating at 1,0 NM): 250 ft

• SRA (terminating at 1,5 NM): 300 ft

• SRA (terminating at 2,0 NM): 350 ft

In such case, either these minimums or OCH are used; whichever are greater.

Final Approach Configuration

For the successful SRA, one of the most important things is to begin the approach in final approach configuration. Since at least 1 NM before passing FAF till touch-down, it is necessary to hold final approach speed (or Vref) and to be in landing configuration, all the time.

Every other modification of approaching speed changes vertical velocity! For the rate of descend determination, it’s useful to use simple rule:

GS [kt] x 5 = VS [fpm].

For example if the ground speed is 150 kt, the rate of descend is 750 fpm. Ground speed is easily recognized by equipment of an aircraft or it could be set as IAS plus/ minus wind correction at the aerodrome.

Utilized Equipment

For the real SRA adventure, it’s very important not to use any navigation equipment (FMC, DME, GPS, VOR, ILS, NDB, etc.). For SRA, just altimeter, horizon, gyroscope and radio are enough.

Final Approach Track

SRA as such begins shortly before passing FAF. SRA ATCo requests not to acknowledge further information and reports passing FAF. At this moment, pilot starts to descend by the calculated VS and listens carefully to the instructions given by SRA ATCo.

Altitude

For every nautical mile, the altitude decrements by approximately 320 ft. Because of rounding, the decrease is 300 ft (sometimes 400 ft) for 1 NM. Thus, don’t get under stress if you altitude is about 100 ft different from recommended one, just slightly modify your VS. Maximal deviation should be 200 ft.

This information is not valid for OCA. Pilot are not allowed to be lower then OCA, any

time.

Unofficial SRA chart for LKTB (never published by Czech authorities, only by Jeppesen company)

Landing Clearance

Landing clearance is delivered during the approach by SRA ATCo (not by TWR). The reason is that the pilot does need to change to a new frequency during the most difficult part of the approach.

SRA ATCo instructs the pilot when and which frequency to contact. It’s usually happens after landing, during vacating the RWY.

Missed Approach

Pilot follows the missed approach procedures if:

• he/ she has not sufficient visual reference at terminal range (RWY or approach light system is not in sight),
• it is not possible to finish the approach at terminal range (aircraft is too high, out of centerline heading, etc.),
• shift from the RWY centerline is too great during the approach,
• a radiocommunication fails,
• he/ she is commanded by ATCo.

Brno Tuřany SRA Procedures

Basic Values

Designation	Value
RWY	09/27
Altitude of Intermediate Approach	3000 ft / 914 m AMSL*
Final Approach Fix	7 NM / 13,0 km from TDZ
Angle of Descent	3°
Terminal Range	2,1 NM / 3,9 km from TDZ
Obstacle Clearance Altitude (OCA)	1430 ft / 437 m AMSL **
Obstacle Clearance Height (OCH)	670 ft / 204 m AGL ***

* Low temperature altitude used from 15 NOV to 15 MAR is 3160 ft/ 960 m unless otherwise published by NOTAM.

** Low temperature altitude used from 15 NOV to 15 MAR is 1480 ft/ 450 m unless otherwise published by NOTAM.

*** Low temperature altitude used from 15 NOV to 15 MAR is 710 ft/ 217 m unless otherwise published by NOTAM.

Radiocommunication Failure

In case of radiocommunication failure, climb to 3000 ft AMSL to BNO VOR and follow radiocommunication failure procedures.

Phraseology

English Phraseology

ATC: This will be surveillance radar approach runway X terminating at Y NM from touchdown, final approach track W degrees, glide path angle V(3) degrees, in case of go around... (continue on hdg X, climb Y and contact Z), obstacle 6 clearance altitude Z ft, check your minimums.

A/C: Surveillance radar approach runway X, minimums checked.

ATC: 2 NM from FAF, reduce to Final Approach Speed and check gear down and locked

A/C: Reducing to final approach speed, gear down and locked.

ATC: 1 NM from FAF, do not acknowledge further transmissions.

ATC: 7 NM from touchdown, commence descent now, establish a 3 degree glide path

ATC: 6 NM from touchdown, altitude should be 2700 ft, heading is good.

ATC: 5 NM from touchdown, altitude should be 2400 ft, right of track, turn 3 degrees to the left, new heading 272.

ATC: 4 NM from touchdown, altitude should be 2000 ft, on track, turn 2 degrees to the right, new heading 274.

ATC: 3,5 NM from touchdown, altitude should be 1890 ft, slightly left of track, turn 2 degrees to the right, new heading 276.

ATC: 3 NM from touchdown, altitude should be 1700 ft, well left of track, turn 3 degrees to the right, new heading 279;cleared to land runway 10, wind 100 degrees 5 knots.

ATC: 2,5 NM from touchdown, altitude should be 1570 ft, closing from the left, continue heading 279.

ATC: 2 NM from touchdown, altitude should be 1410 ft, on track, turn 2 degrees to the left, new heading 276.

ATC: 1,6 NM from touchdown, altitude should be 1270 ft, approach completed.

Czech Phraseology

ATC: Toto bude přiblížení přehledovým radarem na dráhu X končící ve vzdálenosti Y NM od bodu dotyku, úhel trati konečného přiblížení W stupňů, sestupový úhel V(3) stupně, v případě průletu..., bezpečná altitude nad překážkami Z stop, prověřte vaše minima.

A/C: Přiblížení přehledovým radarem na dráhu X, minima prověřena.

ATC: 2 NM od bodu začátku konečného přiblížení, prověřte vysunutí a zajištění podvozku, snižte na přibližovací rychlost.

A/C: Podvozek vysunut a zajištěn, snižuji na přibližovací rychlost.

ATC: 1 NM od FAF, nepotvrzujte další vysílání.

ATC: 7 NM od bodu dotyku, zahajte klesání teď, udržujte sestupovou dráhu 3 stupně.

ATC: 6 NM od bodu dotyku, altitude má být 2700 stop, kurz je dobrý.

ATC: 5 NM od bodu dotyku, altitude má být 2400 stop, vpravo od trati, točte o 3 stupně doleva, nový kurz 272.

ATC: 4 NM od bodu dotyku, altitude má být 2000 stop, na trati, točte o 2 stupně 7 doprava, nový kurz 274. ***

ATC: 3,5 NM od bodu dotyku, altitude má být 1890 stop, mírně vlevo od trati, točte o 2 stupně doprava, nový kurz 276.

ATC: 3 NM od bodu dotyku, altitude má být 1700 stop, hodně vlevo od trati, točte o 3 stupně doprava, nový kurz 279; dráha 10 přistání povoleno, vítr 100 stupňů 5 uzlů.

ATC: 2,5 NM od bodu dotyku, altitude má být 1570 stop, blížíte se zleva, pokračujte kurzem 279.

ATC: 2 NM od bodu dotyku, altitude má být 1410 stop, na trati, točte o 2 stupně doleva, nový kurz 276.

ATC: 1,6 NM od bodu dotyku, altitude má být 1270 stop, přiblížení ukončeno.

*** od 4 NM má ATC trvale zaklíčováno

Abbreviations

Abbreviations

AMSL	Above mean sea level	Nad střední hladinou moře
ASR	Aerodrome surveillance radar	Letištní přehledový radar
ATCo	Air traffic control officer	Řídící letového provozu
DME	Distance measuring equipment	Měřič vzdálenosti
FAF	Final approach fix	Bod konečného přiblížení
FMC	Flight management computer	Počítač systému řízení a optimalizace letu
GPS	Global position system	Globální navigační systém
ILS	Instrumental landing system	Standardní systém přesných přibližovacích majáků
MDA	Minimum descend altitude	Minimální (nadmořská) výška klesání
NDB	Non-direction radio beacon	Nesměrový radiomaják
NM	Nautical mile	Námořní míle
NOTAM	Notice to airmen	Oznámení pro letecký personál
OCA	Obstacle clearance altitude	Bezpečná (nadmořská) výška nad překážkami
OCH	Obstacle clearance height	Bezpečná (relativní) výška nad překážkami
RWY	Runway	Vzletová a přistávací dráha (VPD)
SRA	Surveillance radar approach	Přiblížení přehledovým radarem
SRA ATCo	Surveillance radar approachair traffic control officer	Řídící letového provozu poskytující službu přiblížení přehledovým radarem
TDZ	Touchdown zone	Dotykové pásmo
TWR	Tower	Věž
VOR	VHF omnidirectional radio	Všesměrový radiomaják