P.O. BOX 790490 • SAN ANTONIO, TEXAS 78279-0490 • (210) 824-9421

SUBJECT: REVISION TO SA26-AT DASH ONE AFM

TO: ALL OPERATORS AND AFM MANAGERS OF THE SA26-AT DASH ONE

1. Attached is the Revision dated May 14, 2015 to your AFM.

2. File this transmittal letter in your AFM binder behind the Title Page.

3. Insert Revision 9 Log of Effective Pages behind the Transmittal Letter.

4. Replace Section III Index with revised Index.

5. Replace entire Section III with revised pages.

Section III – INDEX 

MERLIN MODEL SA-26AT

Section III EMERGENCY OPERATING INDEX 

 PROCEDURES

Revised: May 14, 2015

 Page

SINGLE ENGINE PROCEDURES ...........................................III-1

SECURING AN INOPERATIVE ENGINE – CRUISE

 OPERATION ..........................................................................III-1

ENGINE FAILURE DURING TAKEOFF ...................................III-1

 Prior to Liftoff Speed ..........................................................III-1

 After Liftoff with Insuffi cient Runway to Stop ......................III-1

 Single Engine Landing .......................................................III-2

DOUBLE ENGINE FAILURE (RESTARTS/RELIGHTS

 UNSUCCESSFUL) ................................................................III-2

ENGINE - PROPELLER UNCOUPLING ..................................III-3

AIRSTART PROCEDURES ......................................................III-3

ABORTED AIRSTART ..............................................................III-4

ENGINE FIRE – FLIGHT ..........................................................III-4

ENGINE FIRE – GROUND .......................................................III-4

LANDING GEAR MANUAL EXTENSION .................................III-5

SMOKE.....................................................................................III-5

CABIN PRESSURIZATION ......................................................III-5

EMERGENCY EXIT .................................................................III-6

FLAP MOTOR FAILURE ..........................................................III-6

ALTERNATE STATIC AIR SOURCE ........................................III-6

FUEL DUMPING ......................................................................III-7

ELECTRICAL SYSTEM PROCEDURES .................................III-7

BUS FAILURE ..........................................................................III-7

ELECTRICAL SMOKE .............................................................III-7

PROPELLER ANTI-ICE SYSTEM MALFUNCTION .................III-8
FAA APPROVED: JUNE 12, 1968 III-1

MERLIN MODEL SA-26AT

Section III EMERGENCY OPERATING PROCEDURES 

SINGLE ENGINE PROCEDURES

WARNING

IN THE EVENT OF AN ENGINE FAILURE OR POWER LOSS, 

THE ENGINE NEGATIVE TORQUE SYSTEM (NTS) ONLY PROVIDES PARTIAL DRAG REDUCTION BUT NOT TO THE EXTENT 

OF A FULLY FEATHERED PROPELLER.

PILOT MUST TAKE ACTION TO FULLY FEATHER THE PROPELLER (ON THE AFFECTED ENGINE) TO REDUCE PROPELLER 

DRAG.

SECURING AN INOPERATIVE ENGINE-CRUISE OPERATION

 1. Determine inoperative engine by torque or T.I.T.

 2. Secure inoperative engine as follows:

 Engine Stop and Feather ............... PULL

 Generator ........................................ OFF

 Boost Pump .................................... OFF

 Fuel Shut-off Valve ......................... CLOSED

 3. Adjust Power on Operating Engine as Necessary

 4. Retrim

 5. Oil Shutter ........................................... AS NECESSARY

 6. Load on Remaining Generator .......... 200 AMP MAX.

 7. Propeller Synchronizer ...................... LANDING

8. Land as soon as possible, observing landing weight limitations. 

Balance fuel prior to landing by opening crossfl ow valve.

ENGINE FAILURE DURING TAKEOFF

PRIOR TO LIFTOFF SPEED, VLOF

 1. Power levers ....................................... GROUND IDLE

 2. Brakes ................................................. AS NECESSARY

 3. Inoperative engine .............................. SECURE

AFTER LIFTOFF WITH INSUFFICIENT RUNWAY TO STOP

 1. Gear ..................................................... UP

 2. Operating Engine ............................... TAKEOFF RATING

Revised: May 14, 2015
FAA APPROVED: JUNE 12, 1968 III-2

MERLIN MODEL SA-26AT

Section III EMERGENCY OPERATING PROCEDURES 

 AFTER LIFTOFF WITH INSUFFICIENT RUNWAY TO STOP 

(Continued)

 3. Inoperative engine .............................. SECURE

 4. Best Rate of Climb Airspeed ............. 110 KNOTS

 5. Land as soon as possible

 6. If above landing weight, dump fuel.

SINGLE ENGINE LANDING

WARNING

IN THE EVENT OF AN ENGINE FAILURE OR POWER LOSS, 

THE ENGINE NEGATIVE TORQUE SYSTEM (NTS) ONLY PROVIDES PARTIAL DRAG REDUCTION BUT NOT TO THE EXTENT 

OF A FULLY FEATHERED PROPELLER.

PILOT MUST TAKE ACTION TO FULLY FEATHER THE PROPELLER (ON THE AFFECTED ENGINE) TO REDUCE PROPELLER 

DRAG.

 1. Do not extend fl aps until runway is assured.

 2. Do not use reverse thrust on operating engine.

 3. Reduce nonessential electrical loads.

DOUBLE ENGINE FAILURE (RESTARTS/RELIGHTS UNSUCCESSFUL)

 1. AIRSPEED ........................................... MAINTAIN BEST 

 GLIDE AIRSPEED

GLIDE AIRSPEED

 WEIGHT (POUNDS) 10,000 9,000 8,000

 AIRSPEED (KIAS) 130 120 115

NOTE

Best Glide airspeed is approximately 1.4 V/VS.

 2. GEAR ................................................... UP

 3. FLAPS .................................................. UP

Revised: May 14, 2015
FAA APPROVED: JUNE 12, 1968 III-3

MERLIN MODEL SA-26AT

Section III EMERGENCY OPERATING PROCEDURES 

DOUBLE ENGINE FAILURE (RESTARTS/RELIGHTS UNSUCCESSFUL) (Continued)

4. Complete Securing an Inoperative Engine – Cruise Operation 

Checklist.

 Plan for emergency gear extension and a zero fl ap landing. 

If altitude above ground level (AGL) permits, unfeathering 

one engine may provide suffi cient hydraulic pressure to 

operate the fl aps.

ENGINE - PROPELLER UNCOUPLING

WARNING

IN THE EVENT OF ENGINE FAILURE IN CONJUNCTION WITH 

ENGINE UNCOUPLING, REDUCE WINDMILLING DRAG AS FOLLOWS:

IF AN UNCOUPLING EVENT OCCURS WHERE THE ENGINE IS 

OPERATING AND THE PROPELLER IS STOPPED AND FEATHERED, RETARDING THE POWER LEVER TO FLIGHT IDLE MAY 

RESULT IN UNFEATHERING AND SUBSEQUENT ROTATION OF 

THE PROPELLER. IF THIS OCCURS, ADVANCE THE POWER 

LEVER TO MAXIMUM POWER POSITION.

IN THE EVENT OF AN ENGINE WITH AN NTS AND/OR FEATHER VALVE MALFUNCTION, SETTING THE ASSOCIATED 

POWER LEVERS FULL FORWARD WILL DRIVE THE PROPELLER BLADES TOWARD THE FEATHER POSITION YIELDING A 

LOWER WINDMILLING PROPELLER DRAG AND PROPELLER 

SHAFT SPEED.

AIRSTART PROCEDURES

If an engine has been secured because of an obvious failure, 

as indicated by the engine instruments or excessive vibration, 

an airstart is not recommended.

 1. Speed Levers .........................................................MATCHED

 2. Power Levers .........................................................MATCHED

 3. Altitude 20,000' or LESS

 4. Airspeed AS DESIRED

Revised: May 14, 2015
FAA APPROVED: JUNE 12, 1968 III-4

MERLIN MODEL SA-26AT

Section III EMERGENCY OPERATING PROCEDURES 

AIRSTART PROCEDURES (Continued)

 5. Engine Stop and Feather ......................................FORWARD

 6. Fuel Boost Pump ...............................................................ON

 7. Fuel Shutoff Valve .........................................................OPEN

 8. Start Button ............................................. PRESS AND HOLD

 9. Observe Propeller unfeathering

 10. RPM 10–20%

 11. Observe Lightoff by T.I.T. & Fuel Flow

 12. Start Buttons:

RELEASE WHEN T.I.T. STARTS TO RISE 

MAY BE USED AS PRIMER AS REQUIRED

 13. Monitor rpm, T.I.T., until stabilization is attained

 14. Generator ..........................................................................ON

 15. Fuel Pressure, Oil Pressure ..............................GREEN ARC

 16. Oil Shutter .................................................. AS NECESSARY

ABORTED AIRSTART

If lightoff does not occur by 25% rpm or T.I.T. start limit 

of 788 degrees C is reached below 50% rpm, abort start.

 1. Stop Button .................................................................PRESS

 2. Allow engine to windmill for one minute if feasible

 3. Engine Stop and Feather ............................................... PULL

ENGINE FIRE – FLIGHT

WARNING

IN THE EVENT OF AN ENGINE FAILURE OR POWER LOSS, 

THE ENGINE NEGATIVE TORQUE SYSTEM (NTS) ONLY PROVIDES PARTIAL DRAG REDUCTION BUT NOT TO THE EXTENT 

OF A FULLY FEATHERED PROPELLER.

PILOT MUST TAKE ACTION TO FULLY FEATHER THE PROPELLER (ON THE AFFECTED ENGINE) TO REDUCE PROPELLER 

DRAG.

 1. Engine Stop & Feather ................................................... PULL

 2. Fuel Shutoff Valve .................................................... CLOSED

 3. Follow single engine procedures

Revised: May 14, 2015
FAA APPROVED: JUNE 12, 1968 III-5

MERLIN MODEL SA-26AT

Section III EMERGENCY OPERATING PROCEDURES 

ENGINE FIRE – FLIGHT (Continued)

WARNING

DO NOT DUMP FUEL WITH AN ENGINE FIRE. MAKE AN OVERWEIGHT LANDING IF NECESSARY

ENGINE FIRE – GROUND

 1. Engine Stop and Feather ................... PULL

 2. Stop Button ......................................... PRESS

 3. Fuel Shutoff Valve .............................. CLOSE

 4. Starter Test Switch ............................. ENGAGE

 5. Motor Engine by Starter Test Switch until engine is cleared.

LANDING GEAR MANUAL EXTENSION

 1. Landing gear control circuit Breaker ..... PULLED

 2. Airspeed ............................................... 137K MAX.

 3. Gear Handle ......................................... DOWN

 4. Landing Gear Clutch Lever .................. UP

 5. Emergency Hand Pump Lever ............. SLIDE INBOARD

 6. Discontinue pumping when gear indicators show "DOWN" 

or forces noticeably increase.

 7. Do not attempt to retract landing gear after extending by 

the emergency system.

SMOKE

 1. Initiate Descent and Use Oxygen

 2. Set cabin altitude controller to 10,000 feet and Rate control 

to maximum

 3. Determine source of Smoke:

 A. ELECTRICAL SMOKE – See Electrical Emergency Procedures.

 B. BLEED AIR SMOKE – Retard power lever on left engine 

to FLT. IDLE. If smoke stops, secure left engine. If

 smoke continues, place left engine power lever forward

 and right engine power lever to FLT. IDLE. If smoke

 continues, place bleed air switch to SHUTOFF position.

Revised: May 14, 2015
FAA APPROVED: JUNE 12, 1968 III-6

MERLIN MODEL SA-26AT

Section III EMERGENCY OPERATING PROCEDURES 

SMOKE (Continued)

 4. When below 12,000 feet or all occupants are using oxygen,

 additional fresh air may be obtained by placing the

 pressurization switch in the DUMP position. This provides

 ram air supply to the cabin.

CABIN PRESSURIZATION:

If the cabin altitude warning light comes on, the cabin altitude 

is above 11,500. Check differential pressure and controller settings. 

If differential pressure is less than desired, go to "MANUAL" operation. If the desired differential cannot be regained then an excessive 

leak is indicated and it will be necessary to descend or use oxygen.

If the cabin differential pressure exceeds the limit, the outfl ow 

valve controller has failed. Select "MANUAL" position on the 

cabin pressure selector and regulate pressure manually. If manual 

control is ineffective, the fl ight can be continued on the safety valve 

setting. Prior to landing, the cabin pressure differential must be 

relieved by use of the manual control or this alternate procedure.

 1. Altitude ................................................. below 12,000 ft.

 2. Bleed air Shutoff Valve ......................... SHUTOFF

 3. Allow Cabin Pressure to Leak off Until Less Than 1 psi differential Pressure is Shown.

 4. Cabin Pressure Dump Valve ................ DUMP

 5. Bleed air Shutoff Valve ......................... NORMAL

 6. Proceed at Low Altitude to Airport

A third procedure can be used, that of dumping the cabin 

pressure by use of the dump valve. This method is sudden and 

uncomfortable on passengers, and should be used only if other 

methods fail.

If cabin pressure is dumped for any reason while at high 

altitude.

 1. Power Levers ....................................... FLIGHT IDLE

 2. Airspeed ............................................... VMO

 3. Use Oxygen

 4. Descend to 12,000 feet or below

Revised: May 14, 2015
FAA APPROVED: JUNE 12, 1968 III-7

MERLIN MODEL SA-26AT

Section III EMERGENCY OPERATING PROCEDURES 

EMERGENCY EXIT:

 1. Pull Handles Together Then Inward

FLAP MOTOR FAILURE

A Flaps Up Landing will be necessary. Obtain stall speed and approach speed from Figure IV-E.

ALTERNATE STATIC AIR SOURCE:

 1. Select Alternate on static source selector valve. Pilot's 

static instruments will then be vented to the nose compartment. Alternate source position error is less than 4.35 knots 

throughout the operating range.

FUEL DUMPING:

 1. Airspeed ............................................... AS DESIRED

 2. Flaps ..................................................... UP

 3. Fuel Dump Switches ............................ OPEN

NOTE:

Fuel Flow Rate is 230#/Min when dumping from both chutes. 

After dumping desired amount, close fuel dump switches. All 

but 55 gals. in each tank can be dumped. Total dumping capacity is 1849 lbs. of fuel, starting with full tanks. If one dump chute 

fails to open, continue to dump from operative chute and open 

crossfl ow valve. Close dump valves before landing. Observe 50 

Gal. Asymmetric Fuel Limits.

ELECTRICAL SYSTEM PROCEDURES

BUS FAILURE – If one of the essential bus breakers trips due to 

a massive overload on that bus, turn generator off for same side 

and maintain not more than 200 AMPS continuous load on remaining generator.

FAA APPROVED May 14, 2015
FAA APPROVED: JUNE 12, 1968 III-8

MERLIN MODEL SA-26AT

Section III EMERGENCY OPERATING PROCEDURES 

BUS FAILURE (Continued)

NOTE:

Single generator operation will automatically prevent the air 

conditioning compressor from functioning although Auto or Manual 

positioning of the Bleed air Mixing Valve will continue to be operative.

To disable either essential bus, the bus tie switch and generator must be turned off for that side. If either the nonessential 

or air conditioning bus breaker trips due to overload, do not 

attempt to restore power to these busses.

ELECTRICAL SMOKE – If electrical smoke is detected in one 

of the essential busses, turn off the bus tie switch and generator for that side. If smoke subsides, pull all the circuit breakers on the 

affected bus and then turn generator ON. If smoke does not return, 

then place bus tie switch ON. This action will restore full generator 

output to the remaining busses. If the smoke emanates from the 

nonessential bus, turn off the nonessential bus tie switch. If smoke 

comes from air conditioner bus, pull air conditioning control circuit 

breaker. If the main circuit breakers for any of these busses trip, do 

not attempt to reset and follow "BUS FAILURE" procedures.

PROPELLER ANTI-ICE SYSTEM MALFUNCTION

If the propeller boots malfunction as indicated by erratic, low, 

high, or no load conditions on the loadmeter, the system may be 

deactivated by pulling the appropriate circuit breaker for the propeller boot system. If under actual icing conditions, operation may be 

continued as required for safety of fl ight.

FAA APPROVED May 14, 2015