I3303

Approaches
 * 32 to whiting
 * Two PAR's
 * One ASR
 * One no Gyro PAR
 * One Partial Panel PAR (no attitude gyro)

On a PAR you can slow to 90kts when you are told to "contact your final controller." Decision Height is "A height above the highest elevation in the Touchdown Zone, specified for a glide slope approach, at which a missed-approach procedure must be initiated if the required visual reference has not been established. But how do we get a proper altitude? Well, look in the front of the plates at the Radar instrument approach minimums for your approach and remember that according to OPNAV 3710 “Absolute minimums for a single piloted aircraft executing a precision approach are 200-foot HAT and 1/2 statue mile visibility...or published minimums whichever is higher.” So if we look at the South Whiting field minimums we see that the DH is 100' above touchdown. That's 100' too low. So add 100 to the DH (now it's 271).  This is not an issue for ASR, the MDA as published is the MDA.

Do not start your descent on a PAR when the controller says "start your descent;" instead, start descending when he says "on glide slope." At that time you want to begin a 478 fpm (yes 478, I said 450 and was called out on it) descent (aprox. 55% torque). For glide slopes other than 3° consult the chart inside the back cover of any book of approach plates. Once you have established a 478 fpm descent simply moving the cyclic should be enough to correct back on glide slope if you are told you are off of it.

=GCA procedures= PRECISION APPROACH RADAR (PAR) APPROACH (T-34C RI FTI 3880.)

[Brackets] indicate editing for the TH-57C

Reference: NIFM, Chapter 24, &quot;Radar Approaches.&quot; A. 	Amplification - The precision approach radar (PAR) approach uses radar vice aircraft equipment to vector the aircraft to a position for landing during conditions of low ceiling and/or poor visibility. You have been introduced to vectoring procedures during radar vectors to final approach course. During the radar vector procedure, the approach controller used his radar capability to direct your aircraft onto a segment of a standard instrument approach procedure.

During a radar approach, the controller will direct your aircraft to a position from which you can safely land.

Radar approaches fall into two classes:

(1)	Airport Surveillance Radar (ASR) approaches which provide course and range information only and are thus non-precision approaches (these use an MDA)

(2)	Precision Approach Radar (PAR) approaches provide course, range, and glideslope information and can thus be flown to lower minimums using a Decision Height (DH).

This chapter will address PAR's only. The procedures for ASR's are similar but will not be fully discussed until intermediate RI's.

B. 	Procedure

1. 	Preflight - Radar instrument approach minimums are published in the front of FLIP terminal instrument approach procedures (approach plates) and in the minimum section of approach plates if they have radar approaches available. Published information includes the decision height, weather minimums, and glideslope angle. From glideslope angle and groundspeed the pilot can determine the rate of descent required to maintain glideslope on final using the rate of descent table, also in the back of the approach plates.

Familiarize yourself with this information as part of your preflight planning when a radar approach (PAR or ASR) is available at your destination or alternate.

Figure 3-67 is a sample of the section in the approach plates which contains information on radar approaches. For the purposes of illustration, we will consider the PAR approach to runway 36R at Cecil Field NAS.


 * 1) 1. Beside the heading of RADAR is a list of frequencies on which your approach may be used.

- The g's following the frequencies indicate that the radar site has the capability to work on that frequency but does not monitor it continuously. (Additional notes will be found in the radio/nav remarks section of the IFR supplement).


 * 1) 2. 	The runway (RWY), plus any referenced notes.


 * 1) 3. The PAR approach to runway has a glideslope (GS), of 2.5° degrees.


 * 1) 4. The threshold crossing height (TCH), is 35 feet. This means that if you are on glideslope, as you cross the runway threshold, you will be 35 feet above the runway surface.


 * 1) 5. Runway point of intercept (RPI). If you remain on glideslope until touchdown, you will land 800 feet down the runway.


 * 1) 6. Category of aircraft (CAT). &quot;ABCDE&quot; indicates that the published minimums for this approach applies to all five categories of aircraft.


 * 1) 7. Decision Height (DH), Minimum Descent Altitude (MDA) is the MSL altitude of 173 feet in this case. Minimum visibility required for this approach is 1/4 mile. NOTE: Runway Visibility Range (RVR) may be listed if used.


 * 1) 8. Height above touchdown (HAT) and Height above airport (HAA), is the AGL altitude of the published (DH) or (MDA).


 * 1) 9. Ceiling-Visibility, (CEIL-VIS), is used during filing to determine alternate requirements.

OPNAV 3710.7

The T-34 [TH-57C] is considered a single-piloted aircraft. OPNAV indicates that single-piloted aircraft use 200’ ceiling / HAT and _ mile/2400’ RVR as absolute minimums for instrument approaches. (Don't forget about being able to half the visibility since you're a helo pilot! (5.3.5.1 OPNAV 3710.7U) Consider the above example.  When you reach the published decision height of 173’ MSL, you will be at an HAT of 100’ AGL.  In order not to break the 200’ HAT absolute minimum, you must increase the decision height.  In this case, an increase of 100’  is necessary.  This would result in a modified DH of 271’ MSL resulting in a HAT of 200’ AGL.  In addition, the minimum visibility required to commence the approach would become _ mile instead of the original _ mile.

2. 	Initial contact with Approach Control. Your instructor will make the request for PAR approaches upon initial contact with Approach Control. The following approach information will be provided by ATC to aircraft conducting radar approaches:

a.	Type of approach. &quot;This will be a PAR approach to runway 36R.&quot;

b.	Altimeter setting.

c.	Ceiling and visibility if below 1000 feet (or below highest circling minimum, whichever is greater) or visibility less than 3 miles.

d.	Special weather observations.

e.	Airport conditions important to the safe operation of aircraft.

f.	Lost communication procedures, when weather reports indicate that IFR weather conditions will likely be encountered during the approach. Lost communication instructions will typically include an altitude and a standard instrument approach procedure; e.g.

&quot;.... if no transmissions received for 30 seconds (not more than one minute) in the pattern or 5 seconds on final, attempt contact on, and proceed VFR. If unable, proceed with the TACAN 36R approach, maintain 1200 until over the FAF...&quot; (See CECIL NAS TACAN RWY 36R in DOD Volume 12 for illustration.)

3.	Missed Approach. A missed approach instructions will be issued to an aircraft planning a full stop landing, if weather reports indicate that any portion of the final approach will be conducted in IFR conditions. For aircraft planning, a low approach or touch and go, departure instructions will be issued; e.g., &quot;. . . after completing low approach, climb and maintain 1200, turn left heading 270. . . &quot;

When planning a full stop landing, low approach, or touch and go, instructions should be issued by ATC Prior to commencing final descent.

4.	Vectors to the PAR Pattern. When the approach controller picks you up on his scope, his task is to vector your aircraft to a suitable position and altitude for handoff to the PAR final controller. Maintain normal cruise airspeed until a transition is appropriate. If a descent is required, report leaving present altitude and conduct a terminal descent to the assigned altitude. Turns should be performed at standard rate until established on PAR final. Monitor destination navaids as an aid in orientation as well as a means of preparation for the lost communication contingency. If there is a published instrument approach for the same runway you will be performing your PAR; ensure the navaids are tuned correctly and twist the final approach course into the CDI. This will help provide orientation about the airfield and a &quot;backup approach&quot; in the event the radar fails during vectors on final. The controller will advise you of the aircraft's position at least once before starting final, e.g., &quot;. . . downwind leg, 8 miles northeast of airport,&quot; and at least once each mile on final approach, e.g., &quot;. . . 3 miles from touchdown.&quot;

The first PAR approach will normally be demonstrated by your instructor. On this approach you could be vectored to any one of four positions relative to the PAR final: downwind, base, semifinal or final itself. During the subsequent approaches (which you will perform), vectors will follow the &quot;box&quot; pattern.

a.	Vectors to downwind. Depending upon the approach controller's instructions, there are two possible situations once established on the downwind leg.

(1) 	No transition required. Due to traffic considerations ATC may request you maintain an airspeed greater than [90knots]. If you are able, comply with ATC requests and transition to [90 knots] when established on the base leg.

NOTE: This procedure is not intended to limit the pilot's prerogative to alter airspeeds and configurations to meet existing conditions.

(2) 	Transition required. Unless otherwise instructed, when established on the downwind perform a level transition to [90 knots].

NOTE: Army and Navy controllers are required to advise pilots to, &quot;Perform landing checks&quot; while the aircraft is on the downwind leg and in time to complete it before turning base leg. This is done before handoff to the final controller for a PAR approach, or before starting descent on final for a surveillance approach. This is advisory only and not an instruction.

b. 	Vectors to base leg. There are two ways to reach base leg:

(1) Vectors directly onto the base leg from outside the pattern.

(2) Vectors onto the base leg after having flown a downwind leg.

The approach controller should advise you when you reach the base leg. Maintain orientation relative to the field by listening to the controller's position reports, use of available navaids, and the aircraft's heading. For example, the aircraft heading should be approximately 90° to the PAR final course on the base leg.

NOTE: If assigned a lower altitude while in the final approach configuration (FAC), report leaving altitude and perform a [constant airspeed] descent.

c.	Vectors to semi-final. In some cases you will be vectored to a semi-final or a &quot;dog-leg.&quot; Normally on this leg you will be approaching final at a 30-45° angle. If you enter this leg in normal cruise, transition to final approach configuration (FAC) as you would on base leg. In any case, the transition to the final approach configuration should be complete prior to handoff to the PAR final controller. This normally occurs approximately eight miles from the runway.

5.	PAR Final. All procedures described thus far have been used to establish of the aircraft on PAR final. The crux of the entire approach is the ability of the pilot to accurately comply with the final controller's course and glidepath corrections until visually acquiring the runway environment or reaching decision height (DH).

a.	Handoff to the Final Controller. Precision approach radar, though highly accurate, is quite limited in range and azimuth, thus it cannot be used to vector the aircraft to downwind and base legs. You will generally be handed off to the final controller on final or semi-final. The final controller will first conduct a radio check, ask you to confirm your wheels are down, and then continue to assign heading changes to properly position the aircraft on PAR final.

NOTE: Army, Air Force, and Navy controllers will remind the pilot that wheels should be down unless the pilot has previously reported wheels down. &quot;WHEELS SHOULD BE DOWN&quot;. The intent is solely to remind the pilot to lower the wheels, not to place responsibility on the controller.

b.	Maintaining glidepath and course. Once the final controller has established your aircraft on final, he will say, &quot;Do not acknowledge further transmissions.&quot; Further heading changes will be assigned as necessary and at approximately five-six miles from the runway, you will be told &quot;approaching glidepath, begin descent.&quot;

For [TH-57] When you are reported to be &quot;on glidepath,&quot; reduce power and lower the nose to maintain [90] knots. One &quot;technique&quot; used to determine the correct nose attitude is to lower the nose equal to the published glideslope angle.(i.e. If a 3° glideslope angle - lower the nose 3° down). Check for the descent rate previously determined (approximately 400-500 FPM). The final controller will assign corrections to enable you to maintain glidepath and course.

If the aircraft is observed to deviate above or below the glidepath, the pilot is given the relative amount of deviation by use of terms &quot;slightly&quot; or &quot;well&quot; and must adjust his rate of descent to return to the glidepath.

Glideslope corrections

Correct these deviations with coordinated pitch and power changes. Maintain a constant airspeed [90 knots] during the approach. When power changes are required, avoid excessive [collective] movements. Corrections should be made immediately after instructions are given or to return the aircraft to the glidepath. Once established on glideslope with [90] knots, the VSI indicator can be used to detect changes in the rate of descent. Maintain [90] knots with the nose attitude and use small power corrections to adjust the rate of descent. Always check airspeed first, you may be off the glideslope due to your own poor basic airwork.

Heading corrections

The final approach controller will be giving you very precise headings to keep the aircraft on the desired glidepath. Accuracy of heading is extremely important and the controller expects the pilot to maintain these headings. When instructed to make heading changes, make them immediately.

Instructions prior to each turn are preceded by the phrase &quot;turn right&quot; or &quot;turn left&quot; followed by the new heading.

To prevent overshooting, the angle of bank should approximate the number of degrees to be turned, not to exceed a one-half standard rate turn. After a new heading is directed, the controller assumes it is being maintained. Additional heading corrections will be based on the last assigned heading.

Keep the balance ball centered.

6.	Missed Approach - A missed approach must be executed when you reach decision height (DH) if the runway environment is not in sight.

NOTE: After reaching Decision Height (DH), the precision final controller will continue, to provide course and flight path information until the aircraft passes over the landing threshold. This information is strictly advisory in nature.

Additionally, a missed approach must be executed when any of the following occur:

a. When instructed by the controller when runway environment is not in sight.

NOTE: Decision Height occurs on your barometric altimeter or when advised by the final controller, whichever occurs first.

b. When directed by tower, wheels watch, or runway duty officer.

c. When a safe landing cannot be made.

Missed approach or low approach/climbout procedures vary with the field location, traffic conditions and the duty runway. Detailed procedures are covered by the controller on each PAR. This portion of the approach will usually be executed by the instructor.

=AIRPORT SURVEILLANCE APPROACH (ASR APPROACH) (T-34C RI FTI 4400.)= [Brackets] Indicate editing for the TH-57C Reference: AIM Chapter 5, Section 4, &quot;Arrival Procedures;&quot; NIFM Chapter 24; &quot;Surveillance Final Approach.&quot;

A. 	Amplification - A surveillance approach is a non-precision approach in which the controller provides navigational guidance in azimuth only. The surveillance approach, like the PAR approach, is a special instrument approach procedure and as such will not be described in the approach plates. Procedures prior to the surveillance final are exactly the same as a PAR. Refer to the section on PAR for a review of these procedures. Airport surveillance radar is less precise than precision radar in its position determining capability. Surveillance radar also lacks altitude readout. This accounts for the higher minimums on ASR approaches. It is a good practice to &quot;back up&quot; any radar approach with a published Non-Precision approach if possible.

B. Procedure 1. 	Preflight - Refer to the FLIP Terminal Instrument Approach Procedures (Approach Plate) for minimum descent altitude (MDA) and weather minimums if a surveillance approach is available at your destination or alternate. These will be listed under the subheading &quot;ASR&quot; (Airport Surveillance Radar) in the PLAN VIEW in the communications section on the approach plate, and the &quot;Radar Instrument Approach Minimums&quot; section in the front of the approach plates. Unlike a PAR, a surveillance approach may be terminated as a circle to land maneuver. If this is the case, the minimums could vary with aircraft category.

2. 	Initial Contact With Approach Control - Following contact with the agency controlling the approach, you will, as in -the PAR, be vectored to downwind, base, or semi-final/final. Missed approach/low approach procedures and lost communications instructions should be written down when given. Transition to the landing configuration as in the PAR pattern. The controller will specify the runway to which the approach will be conducted, the MDA, and the missed approach point. An example of this transmission follows:

APC CONT:	&quot;Navy (Call sign), Approach, these will be vectors for a surveillance approach to runway 7R at Sherman Field. Published minimum descent altitude 4Q, missed approach point one-half mile from the runway.&quot;

NOTE: Recommended altitudes will be furnished each mile on final if requested by the pilot.

3. 	ASR Final - The same radar used to vector the aircraft to final is used to align the aircraft on course to the runway. Therefore, in many cases, you will not be handed off to a final controller.

At approximately five to six miles from the runway, you will be instructed to &quot;descend to minimum descent altitude.&quot; At this time, reduce power and lower the nose to maintain [90] knots in a 400-500 FPM rate of descent. No glidepath advisories will be given but, if requested by the pilot, recommended altitudes will be furnished at one mile intervals. Although not required, try to fly the recommended altitudes, as they approximate the PAR glideslope. 25 feet prior to the MDA, add power [trim the nose for 90 knots], and maintain the MDA until told &quot;at missed approach point.&quot;

4. 	Missed Approach - Missed approach/low approach procedures vary with the field location, traffic conditions, and duty runway. Detailed procedures are covered by the controller on each GCA.

NOTE: There is such a thing as a NO-GYRO ASR approach. If required to fly one, comply with the controllers instructions to make “standard rate” or “half standard rate” turns. Once on final, descend to the MDA like a normal ASR approach, but using half standerd rate turns, as directed by ATC.

=NO GYRO PRECISION APPROACH (T-34C RI FTI 4500.)= [Brackets] Indicate editing for the TH-57C.

Reference: NIFM, Chapter 24, &quot;Radar Approaches;&quot; AIM, Chapter S, Section 4, &quot;Arrival Procedures.&quot;

A. 	Amplification - The No Gyro Precision Approach is a precision approach flown without the use of an RMI. In this case the word &quot;gyro&quot; refers to your directional gyro, which provides input to the RMI. It is conceivable that during flight your RMI could fail while all other systems essential to flight remain normal. Under such conditions, it would be impossible to perform instrument navigation or execute a published instrument approach (funny, isn't that what the last two flights were about?). However, if you are under radar contact ATC can perform a service which will enable you to navigate safely under instrument conditions without an RMI. This service is a no gyro vector. How can you fly a radar vector with no RMI? The answer is simple if you consider that:

1.	The radar controller can observe the track you are making over the ground and adjust that track by assigning headings to fly.

2.	Your aircraft has a turn needle (assumed to still be operating).

3.	Your aircraft has an operating attitude gyro.

The radar controller, knowing your present track, can apply a procedure very similar to the timed turns you learned in BI's. In this case the controller tells you to start and stop turns and performs the timing between starts and stops.

These no gyro vectors can be used to vector you to VFR conditions for a visual landing or to vector you through a ground controlled approach. This section will address the no gyro PAR. It is a good practice to &quot;back up&quot; any radar approach with a published Non-precision approach if one is available.

Since the no gyro approach is primarily designed as a response to an inflight equipment failure, preflight planning will be limited. The same glideslope and DH that apply to the standard PAR also apply to the no gyro approach. This information should be reviewed prior to any GCA.

B.	Procedure-

1. 	The no gyro PAR is procedurally similar to the normal PAR and this section will address only the differences. Carefully review the section on PAR approaches and PAR minimums in the approach plates.

2. 	Initial contact with approach control for the practice no gyro approach will normally be made by the instructor. Just like the standard PAR, ensure that you have the current &quot;WAR&quot;, missed approach instructions, and if the field is IFR, lost communications procedures.

3. 	As discussed in the PAR approach, you may be vectored to semi-final, base, downwind, or you may already be established in the GCA box pattern. You should make all turns at standard rate until on final approach where you will be advised to make turns at half standard rate. Roll into turns immediately upon hearing the words &quot;turn right&quot; or &quot;turn left.&quot; Roll wings level on receipt of the words &quot;stop turn.&quot; During the approach, repeat all altitudes, turns, stop turns, and altimeter settings. Acknowledge all other instructions unless otherwise advised.

NOTE: The wet compass may be used for orientation during the no gyro approach. A heading roughly reciprocal of the runway would indicate downwind; a perpendicular heading would likely mean base leg. Use this compass only for orientation and not for maintaining heading. Orientation in the pattern can also be maintained with reference to ATC position reports and navaid use at the airfield.

4. 	Transition to final approach configuration as described in the section on PAR approaches. Report the landing checklist, item by item, to your instructor over the ICS. If a descent is required in the final approach configuration reduce power, lower the nose, and maintain airspeed. All turns prior to final will be at standard rate.

5. 	You will be handed off to the final controller either on final or on semi-final. Communications will be similar to the handoff on a normal PAR except you will be told &quot;You're on final, make all turns half standard rate.&quot; When you are reported to be &quot;on glidepath&quot;, gradually reduce power and lower nose to maintain glideslope and [90] knots. Start half standard rate turns when instructed by the final controller. Follow the controller's directions carefully and maintain glidepath and course.

6. 	At the decision height (DH), if the field is in sight and the aircraft is in a position to make a safe landing, descent below DH to landing is authorized. If both conditions are not met, execute missed approach. This will be performed by the instructor.

=GROUND CONTROLLED APPROACHES (GCAs): PARs and ASRs (TH-57 FTI 914.)= A.	Maneuver Description and Application [Reference: NIFM Chapter 24 (RADAR APPROACHES), AIM Chapter 5 Section 4 (Arrival Procedures) Chapter 5 Section 5 (Pilot/Controller Roles and Responsibilities)]

Radar control is one of the most precise methods used for accomplishing an instrument approach. A radar controlled approach provides positive separation, sequencing for landing, and assistance in navigation for the pilot during the approach.

A radar approach is accomplished by a controller providing course, glide slope, and range information. The two types of radar approaches are the precision approach (PAR) and the surveillance approach (ASR).

Both the precision and surveillance approach begin with radar positioning or vectors to the final approach course utilizing surveillance radar. During this &quot;transition to final&quot; segment, the controller directs heading and altitude changes as required to position the aircraft on final approach.

Both types of GCAs are ground controlled radar approaches, but the PAR is a precision approach and the ASR is not. The primary difference between the two is that glideslope information is provided to the pilot during a PAR but not during an ASR. Consequently, landing weather minima are higher for an ASR than a PAR. Although no glideslope information is available during an ASR approach, the pilot may request the controller to provide recommended altitudes on final.

B.	Procedures

1.	OBTAIN WEATHER, ALTIMETER, AND DUTY RUNWAY (WAR) IF ATIS IS NOT AVAILABLE.

2.	TUNE AND IDENTIFY NAVAIDS.

3.	TIMING IS NOT REQUIRED.

4.	BRIEF THE APPROACH AND COPILOT DUTIES.

5.	OBTAIN APPROACH CLEARANCE.

6.	MAINTAIN 100 KIAS UNTIL GIVEN THE INSTRUCTIONS, &quot;CONTACT FINAL CONTROLLER.&quot; AT THAT TIME TRANSITION TO 90 KIAS AND COMPLETE THE LANDING CHECKLIST.

7.	WHEN DIRECTED TO TURN OR DESCEND BY THE CONTROLLER, EXECUTE AS SOON AS THE INSTRUCTIONS ARE RECEIVED.


 * PAR: THE PAR STARTS WHEN THE FINAL CONTROLLER INFORMS THE PILOT THAT HE IS ON FINAL. WHEN THE CONTROLLER ADVISES THAT THE AIRCRAFT IS ON GLIDESLOPE, ADJUST POWER TO ESTABLISH THE PREDETERMINED APPROXIMATE RATE OF DESCENT WHILE MAINTAINING BOTH AIRSPEED AND ASSIGNED HEADING.


 * ASR: WHEN CLEARED TO DESCEND TO THE MDA, ADJUST THE RATE OF DESCENT TO ENSURE REACHING THE MDA BEFORE REACHING THE MISSED APPROACH POINT (MAP) WHICH IS USUALLY LOCATED ONE MILE FROM THE LANDING THRESHOLD.

8.	EXPECT LANDING CLEARANCE TO BE RELAYED THROUGH GCA CONTROLLER AT 3 NM

=GCA lost communications=

FIH A-7

4. RADAR APPROACHES - initiate lost communications procedures if no transmissions are received for approximately one minute while being vectored to final, 15 seconds while on ASR final approach, or five seconds while on PAR final approach.

a. Attempt contact on a secondary frequency, the previously assigned frequency, the tower frequency, or guard.

b. If unable to re-establish communications and unable to maintain VMC, proceed with a published instrument approach procedure or previously coordinated instructions. Change transponder to appropriate codes.

c. Maintain the last assigned altitude or the minimum safe/sector altitude ( emergency safe altitude if more than 25 NM             from the facility), whichever is higher, until established on a segment of the published approach.

=AFCS requirements for IMC flight= REQUIRED EQUIPMENT FOR IMC	FLIGHT (NATOPS 4.18) The following equipment must be operative prior to entering instrument meteorological conditions in the TH-57C:

1. 	Cyclic force trim system

2. 	Ministab flight control system (pitch and roll)

Check out FAR/AIM Chapter 10 Section 1, talks all about FAA helicopter control and stabilization requirements for helo IFR operations.

=Low fuel state during IMC= (Skinner Gouge RI-6S) Whenever an aircraft is in a situation where there is not enough fuel for the safe completion of an IFR flight plan it is an URGENT situation. This situation can arise for a number of different reasons: fuel system malfunctions, poor preflight planning, unexpected ATC holding or divert instructions, unforecasted severe weather, or any other unforeseen situation.

According to the Flight Information Handbook, a situation of urgency is defined as a condition concerning safety of an aircraft or other vehicle, or of some person on board or within sight but does not require immediate assistance (e.g. lost, fuel shortage, partial engine failure, etc.)

Transmit an URGENCY CALL or “PAN PAN” report and use a modified ISPI format. Identification, situation – fuel state (fuel remaining in hours and minutes), Position, and intentions. Request assistance or clearance for an approach to a local airport.

Minimum Fuel - Indicates that an aircraft's fuel supply has reached a state where, upon reaching the destination, it can accept little or no delay. This is not an emergency situation but merely indicates an emergency situation is possible should any undue delay occur. (GP 2-28)

=Hydraulic system malfunctions= Hydraulic System Failure

INDICATIONS:

HYDRAULIC PRESSURE light & Increased force required for control movement Feedback in control.

PROCEDURES:

1. Airspeed — Adjust (to obtain most comfortable control movement level). 2. HYDRAULIC BOOST switch — Check ON. 3. HYD BOOST circuit breaker — Out. If system is restored:

4. Land as soon as practicable. If system is not restored:

5. HYD BOOST circuit breaker — In. 6. HYDRAULIC BOOST switch — OFF. (C)7. FORCE TRIM (FT) — ON. (C)8. AFCS STAB — ON. (C)9. AFCS ALT — OFF. 10. Land as soon as practicable.

Hydraulic Power Cylinder Malfunction

INDICATIONS: Cyclic/collective control displaces to abnormal position Pilot control of cyclic/collective difficult or impossible

PROCEDURES:

1. HYDRAULIC BOOST switch — OFF. WARNING Hydraulic system will not secure if HYD BOOST circuit breaker is out.

2. Helicopter — Regain Control. Adjust airspeed as desired to obtain most comfortable control movement level.

3. Land as soon as possible. WARNING In the event of a complete power failure in the TH-57B or a failure of the ESS No. 2 bus in the TH-57C, the hydraulic system will reenergize in the malfunction mode. The pilot will be unable to override the hydraulic boost solenoid.