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      AMCPAM 10-6 1 JUN 95 5-1

      CHAPTER 8

      KC-10 AIR REFUELING

      Link to Falcon 4 Specific Refuel Information

      GENERAL

      Receiver air refueling is integral to the mission of the KC-10. During operational missions short tracks, large onloads, and weather often combine to make a "fun" thing rather difficult. Good techniques and an understanding of the basics involved in receiver AR will help you effectively accomplish this task.

      No one KC-10 pilot uses all the references and techniques listed in this chapter. One of the advantages of the KC-10 over other large receiver aircraft is the visibility from the cockpit. Scan the entire tanker and fly formation off it. While specific references may vary slightly depending upon your seat position and height, don't get lazy. Keep your eyes moving. Experiment and pick references and/or techniques that work the best for you. Practice may not make perfect, but it will make you a better receiver pilot.

      AERODYNAMIC CONSIDERATIONS

      Receiver air refueling is no more than flying close trail formation off the tanker. During formation flying, airplanes in close proximity will produce mutual interference in airflow patterns and alter the aerodynamic effects on each of the aircraft. One effect is the tendency of the airplanes to be drawn together. The closer the airplanes come to one another, the stronger the effect. The tanker will experience an effect which will be somewhat similar to encountering ground effect, i.e. a reduction in induced drag- - less downwash at the tail and a nosedown pitching movement. The receiver aircraft will experience increased induced drag -- increased downwash at the tail and a pitching movement noseup. The pilot feels these aerodynamic effects as changing control force requirements as the aircraft relative positions change. If the relative position of the two aircraft is changing rapidly, the control force requirements will also change rapidly. Compared to other large receiver aircraft, the KC-10 flight controls are much lighter and more responsive. It is important to make smooth, yet positive, pitch, power, and lateral control changes during air refueling. Avoid over- controlling.

      The receiver feels the downwash from the number two engine of the KC-10 tanker in his control column and rudder pedals. This effect becomes more pronounced the higher the receiver gets behind a KC-10 tanker. You will usually first feel the upper edge of the envelope through a "chattering" of the rudder pedals. The downwash created by the number two engine contributed to fatigue cracks around the upper rudder. For this reason it is not a good technique to ride high in the envelope (above 26 degrees elevation) when refueling from another KC-10.. Fatigue cracks found around the upper rudder have been attributed to the downwash caused by the number two engine.

      RENDEZVOUS

      The air refueling manuals discuss rendezvous procedures in detail. Good techniques can assist in the rendezvous and closure. Maintain airspeed, altitude, and course. Use the autothrottles and autopilot. , because T they reduce pilot workload and allow concentration on the rendezvous itself.

      Watch the closure visually and/or electronically to avoid the overrun. Timing is useful as a backup and for situational awareness during the tanker’s final turn. Hack the clock when the tanker is at the calculated turn range. A KC-135 should be 1/2 way through the turn at 1 min and rolled out down track at 2 min (30 degree bank turn). A KC-10 will use 75 seconds and 150 seconds, respectivelyfully (25 degree bank turn).

      If it appears the tanker will be closer than 1/3 of the turn range when 1/2 way through the turn, an overrun is likely. To avoid a "tail-chase" the receiver should ensure the tanker is heading down track (based on timing in IMC conditions) before making any aggressive heading corrections towards the tanker. Often the rendezvous can be saved simply by The receiver can help minimize an anticipated overrun by slowing down until the tanker has forward spacing; however, the receiver should initiate overrun procedures if required to slow more than 25 knots. Keep in mind the training lost for the tanker if you "save" the rendezvous by slowing down early—they’ll think they’ve accomplished a wonderful rendezvous.

      AMCPAM 10-6 1 JUN 95 5-2

      RADAR

      Good use of radar has saved many a been a valuable aid in many rendezvous. EMCON considerations, in conjunction with weather, will determine prudent use of radar on each sortie. If possible, practice using the radar as if visibility was 1 NM. This will help ensure you have the skills needed to effect that critical rendezvous while in the weather.

      Identify the tanker's beacon as soon as possible. This may occur well beyond 150 NMs. If weather is a factor, revert to WX mode as necessary to ensure safety throughout the rendezvous. Assuming the tanker is above you, search with the antenna tilt about 1/2 degree up (above zero tilt) and the gain in Auto. If you do not see a beacon when you can reasonably expect one, switch to the other radar system. Once you spot a likely beacon, switch to the minimum range that will keep it on the scope. Slew a marker out to just short of the beacon, then select the delay function and 25 NM range. Once you have identified your tanker, select the normal function and the appropriate range. Track the beacon, selecting smaller ranges when able.

      Determine a ball park tilt used to paint a target by dividing the altitude differential in hundreds of feet by the range in NMs. For example use a .4 degree tilt should be used if the tanker is at FL 270 and receiver is at FL 260 at a 25 NM range (270 - 260 divided by 25 = 10/25 = .4 degree tilt).

      During the rendezvous the tanker should track down (or very close to) the left 30 degree line on the radar scope. If the tanker’s radar return approaches the 60 degree line an overrun is likely.

      Using skin paint during the final stages of a rendezvous will be helpful in determining the exact location of the tanker. At 25 NMs, select 25 NM range and the WX mode and attempt to skin paint the tanker. If not immediately visible, vary the tilt in 1/4 to 1/2 degree increments and allow several sweeps between variations. Switch between BCN and WX as necessary until achieving skin paint. The tilt required will increase as the range decreases, so that by 5 NMs it is approximately 2 degrees above zero tilt.

       

      At 5 NMs, change your radar range and select MAP 1, pencil mode. If a target is not visible, vary the tilt to acquire the tanker. You may need to select fan mode and increase the tilt 2 degrees to account for the changed beam. When acquired in the fan mode you may revert to pencil beam, decrease the tilt 2 degrees, and continue to track the tanker.

      At 3 NMs, the tanker should be on course and the tilt should be about 3 degrees above zero tiltup. This is a good time to start the prep for contact checklist. Concentrate on giving the pilot flying a good "Inverted PAR" to the tanker.

      Use only small heading changes to get in the tanker's six. HDG SEL works great for this. Remember Heading Select references Mag Heading and you are probably still in INS. A technique is to place the tanker's planned roll-out heading in the HDG SEL window prior to the rendezvous. -- (iIf you did coordinated the tanker's planned roll-out heading that on the day before when you discussed your EMCON procedures., didn't you;? iIf not, check your RMI for a mag heading while the auto pilot is flying the IP-CP line.) in the HDG SEL window prior to the rendezvous. The copilot then provides heading changes to the pilot in terms of degrees of turn - left or right. As the receiver aircraft approaches one NM and starts to climb, the Rradar should be in MAP 1 with the tilt set about 10 degrees. Concentrate on giving the pilot flying a good "Inverted PAR" to the tanker. Remember these are target tilts and will vary between sets. A 1/4 degree of tilt can make a big difference in target acquisition, so don't be afraid to make small tilt corrections, up or down, if you lose the target.

      CLOSURE

      If everything has gone according to plan, you should now be one mile in trail and 1000 feet below the tanker at 305 KIAS (figureFigure 5-1). With If you elect to leave thethe autopilot and autothrottles engaged, select 200 - 300 feet-per-minute up on the vertical speed wheel. Continue the "Inverted PAR" except instead of a set rate-of-descent, and establish a set rate-of climb. Use a target of 100 feet of climb per 1/10th NM, keep the tanker in center of the windscreen and the boom nozzle on the tanker's nose. At .6 NM set 300 KIAS and let the speed stabilize. Disengage the command mode of the autopilot and ATS prior to .5 NM and ensure the FE has called checklist complete prior to closing within .5 NM. As the aircraft approaches pre-contact, start looking for the UHF antenna on white line (KC-135) or the VHF antenna on the nose (KC-10). Continue up the "30 degree line" with the "Inverted GCA" until reaching pre-contact. (See figureFigure 5.-2).

      CLOSURE— - NIGHT

      References and techniques for night are generally the same for day. However, at night there may be some problems picking up the actual boom nozzle at 1/2 NM. Approximate the boom nozzle by keeping the tanker in the middle of the windscreen or putting the boom marker light on the tanker nose. A common technique is to use certain lights to form "equilateral triangles" to judge elevation (figureFigure 5.-5). The KC-135's underbody illumination lights and the tail navigation light form the first or "Big Triangle." The underwing and boom marker lights form the "Small Triangle." Maintain the geometry of the large triangle until approximately 300 feet. Use the smaller triangle as an aid in closure from 300 feet. It starts out as an inverted triangle and then flattens out and expands to form an upright equilateral triangle approaching pre-contact. Precontact is easily identified when the tail or "stinger" light of the KC-135 is just out of sight of the top of the windscreen. Technique is to set the salmon bug on 290 KIAS and have the copilot verbalize speed deviations of ± 5 knots. The tendency here is to allow the speed to decay below 290 KIAS while concentrating on the tanker. Finally, figureFigures 5.-3 and 5.-4 identify KC-135 and KC-10 lighting, respectively. Use proper terms if tanker lighting requires adjustment.

      PRECONTACT

      There are at least three key things a pilot must master to become proficient in air refueling. The first is flying a good, stable precontact. The second is good power control and the third is trim. Stabilize behind the tanker with no closure and trim the airplane, both in pitch and roll. Trim out the pressures until you feel comfortable. Most pilots prefer the airplane trimmed to a neutral setting. A few like a nose heavy airplane and hold slight back pressure. The goal is to be comfortable. A heavy yoke and a white knuckle grasp will lead to fatigue during a long, heavy-weight onload.

      Try to stabilize 50 feet aft of the boom nozzle at approximately 28 degrees (KC-135) to 30 degrees (KC-10) elevation. Place the UHF antenna on the white line (or 2nd row of rivets if the line is missing). On the KC-10 place the bottom of the water drain mast on the nose gear door or cover 2/3 of the VHF antenna with the fuselage (1/3 of the antenna below the nose). This will provide an elevation reference. Use the yellow centerline stripe to align the azimuth. Also use the boom and director light panels to aid in azimuth alignment. A fore and aft reference is achieved by positioning the boom pod in the upper portion of the windscreen. The end of the boom nozzle should be in the center of the windscreen and appear about the size of a small grapefruit or baseball. Most importantly, fly formation with the tanker. Use his wings as a roll reference. Maintaining the same amount of sky above each wing will keep your wings level relative to the tanker.

      CONTACT

      Moving from pre-contact to contact requires patience and the ability to place the airplane exactly where you want it. Don't rush that first contact. Stabilize in the pre-contact position, take a deep breath and relax. Run a mental checklist to prepare for closure. Is your seat positioned properly? Is the aircraft trimmed? Has the AR announcement been made and the crew and passengers seated with their seat belts fastened? Is the Ready Light On? Is the tanker ready? Only after answering yes to your checklist questions are you ready to refuel.

      In the KC-10, especially at training weights, be judicious with your power, as a little throttle can go a long way. Think in terms of 1/2 or even 1/4 knob-widths of power. Make a power application, trim, and wait for movement. Don't become impatient and make a second or third throttle movement before the first has a chance to take effect. You are trying to move a great deal of mass and it takes time to overcome the inertia of this mass. If your aircraft is heavy and closing faster than two foot per second, it's going to take a large power reduction to stop its forward momentum. Conversely, it will also take a large power change to stop a rapid movement aft. Large power changes require large trim changes. Rushing the closure, too much power, and not trimming will almost always result in the pilot getting behind the aircraft, developing pilot induced oscillations, and failing to make a contact. Once again power control, trim, and patience are the keys.

      AMCPAM 10-6 1 JUN 95 5-3

       

       

      Figure 5.-1.: Closure —- 1 NM.

       

      "INVERTED PAR"

      RULE: CLIMB 100 FEET PER 1/10 NM STARTING

      1000 FEET BELOW AND 1 NM BACK FROM TANKER.

       

      Figure 5.-2.: Inverted PAR.

       

       

      AMCPAM 10-6 1 JUN 95 5-4

      CLOSURE - NIGHT

      References and techniques for night are generally the same for day. However, at night there may be some problems picking up the actual boom nozzle at 1/2 NM. Approximate the boom nozzle by keeping the tanker in the middle of the windscreen or putting the boom marker light on the tanker nose. A common technique is to use certain lights to form "equilateral triangles" to judge elevation (Figure 5-4). The KC-135's underbody illumination lights and the tail navigation light forms the first or "Big Triangle." The underwing and boom marker lights form the "Small Triangle." Maintain the geometry of the large triangle until approximately 300 feet. Use the smaller triangle as an aid in closure from 300 feet. It starts out as an inverted triangle and then flattens out and expands to form an upright equilateral triangle approaching pre-contact. Technique is to set the salmon bug on 290 KIAS and have the copilot verbalize speed deviations of ± 5 knots. The tendency here is to allow the speed to decay below 290 KIAS while concentrating on the tanker. Finally, Figures 5-3 and 5-4 identify KC-135 and KC-10 lighting respectively. Use proper terms if tanker lighting requires adjustment.

      PRECONTACT

      There are at least three key things a pilot must master to become proficient in air refueling. The first is flying a good, stable precontact. The second is good power control and the third is trim. Formate on the tanker with no closure and trim the airplane, both in pitch and roll. Trim out the pressures until you feel comfortable. Most pilots prefer the airplane trimmed to almost hands off. A few like a nose heavy airplane and hold slight back pressure. The goal is to be comfortable. A heavy yoke and a white knuckle grasp will lead to fatigue during a long, heavy-weight onload.

      Try to stabilize near 50 feet aft of the boom nozzle at approximately 28 degrees (KC-135) to 30 degrees (KC-10) elevation. Place the UHF antenna on the white line (or 2nd row of rivets if the line is missing). On the KC-10 place the bottom of the water drain mast on the nose gear door or cover 2/3 of the VHF antenna with the fuselage (1/3 of the antenna below the nose). This will provide an elevation reference. Use the yellow centerline stripe to align the azimuth. Also use the boom and director light panels to aid in azimuth alignment. A fore and aft reference is achieved by positioning the boom pod in the upper portion of the windscreen. The end of the boom nozzle should be in the center of the windscreen and appear about the size of a small grapefruit or baseball. Most importantly, fly formation with the tanker. Use his wings as a roll reference. Look for the jackscrew housings, bumps, on the top of the KC-135 wings. Maintain the same amount of sky above each wing will keep your wings level relative to the tanker.

      CONTACT

      Moving from pre-contact to contact requires patience and the ability to place the airplane exactly where you want it. Don't rush that first contact. Stabilize in the pre-contact position for 30 seconds, take a deep breath and relax. Run a mental checklist to prepare for closure. Is your seat positioned properly? Is the aircraft trimmed? Are you in pre-contact position? Has the AR announcement been made and the crew and passengers seated with their seat belts fastened? Is the Ready Light On? Is the tanker ready? Only after answering yes to your checklist questions are you ready to refuel.

      In the KC-10, especially at training weights, be judicious with your power, as a little throttle can go a long way. Think in Terms of 1/2 or even 1/4 knob-widths of power. Make a power application, trim, and wait for movement. Don't become impatient and make a second or third throttle movement before the first has a chance to take effect. You are trying to move a great deal of mass and it takes time to overcome the inertia of this mass. If your aircraft is heavy and closing faster than one foot per second, it's going to take a large power reduction to stop its forward momentum. Conversely, it will also take a large power change to stop a rapid movement aft. Large power changes require large trim changes. Rushing the closure, too much power, and not trimming will almost always result in the pilot getting behind the aircraft, developing pilot induced oscillations, and failing to make a contact. Once again power control, trim and patience are the keys.

      AMCPAM 10-6 1 JUN 95 5-5

      KC-135 EXTERIOR LIGHTING

      1. NOSE LANDING AND TAXI LIGHT

      *2. NACELLE ILLUMINATION LIGHT (TYPICAL) (2 PLACES)

      3. TAXI LIGHT (2 PLACES)

      4. LANDING LIGHT (FIXED) (2 PLACES)

      *5. NAVIGATION POSITION LIGHTS (7 PLACES)

      * 6. UNDERWING ILLUMINATION LIGHT (TYPICAL)

      7. ROTATING/RENDEZVOUS BEACON LIGHTS (2 PLACES)

      *8. UNDERBODY ILLUMINATION LIGHT (TYPICAL)

      9. TERRAIN LIGHT (RETRACTABLE)

      *10. RECEIVER PILOT DIRECTOR LIGHTS

      11. BOOM MARKER LIGHTS (FLUORESCENT)

      *12. BOOM NOZZLE LIGHT

      *13. A/R FLOOD LIGHTS

      * DESIGNATES ADJUSTABLE LIGHTING

      Figure 5.-3.: KC-135 Exterior Lighting (T.O. 1-1C-32).

      AMCPAM 10-6 1 JUN 95 5-6

      KC-10 EXTERIOR LIGHTING

      1. Director Lights 10. Forward Fuselage 16. LOGO Lights 23. Fuselage Landing

      2. Outboard Pod Underbody Lights 17. Formation Light Light (typical)

      Markings Illumination 11. Inboard Pod Markings (typical) 24. Slipway Flood

      Light Illumination Light 18. Aft Position Light Lights

      3. High Intensity 12. Aft Fuselage White (typical) 25. Lead-in Stripes/UARRSI

      Supplemental Underbody Light 19. Formation Lights Electroluminescent

      Lights (typical) (typical) (typical) Lighting System

      4. Horizontal Stabilizer (Inboard Side of 20. Forward Position 26. Formation Light

      Illumination Light Outboard Flap Hinge Light, Red (typical)

      (typical) Fairing) 21. Taxi and Runway 27. Forward Position

      5. Receiver Aircraft 13. Lower Anti-Collision/ Turnoff Light- Light, Green

      Floodlights Rendezvous Light Ground Flood 28. Upper Anti-Collision/

      6. Boom Marker Lights 14. Nose Landing (typical) Rendezvous Light

      (Fluorescent) Gear Lights 22. Wing and Engine 29. Upper Fuselage

      7. Boom Nozzle Lights 15. Formation Light Scan Light (typical) Floodlights

      8. Hose/Drogue signal (typical)

      Lights

      9. Wing Illumination

      Lights

       

      Figure 5.-4. : KC-10 Exterior Lighting (T.O. 1-1C-32).

       

      AMCPAM 10-6 1 JUN 95 5-7

      Maintain your ""30 degree line"e" references as you move towards contact. Nearing 20 feet, the receiver bow wave and tanker/boom downwash meet. This may become more pronounced while closing from 20 to 5 feet. At times, the bow wave and tanker downwash may cause closure to slow down or even stop. If you stagnate, a small power addition should push you through. Also at this point the bow wave may force the tanker's tail to rise. This will appear as if you are going low in the envelope. Do not make a large pitch up correction. Allow the tanker autopilot or pilot, if autopilot off, to compensate and level off. (As you close, the boom nozzle will go out of view at about 10 feet.)

      At approximately 5 feet you will begin to hear air rushing by the boom nozzle. This becomes very pronounced just prior to contact. A technique used by some boomers is to start flashing the red "forward light" as you approach ten feet and increase the frequency of the flash the closer to contact. At about 3 feet, or when the red forward light goes out, reduce power slightly to stabilize in the contact position and wait for the boom to make contact. Your throttle position should be about the same required to fly precontact. Again be patient and don't make unnecessary corrections in power or elevation. Wait for the director lights to come on and make corrections as needed. The contact position, and formation flying in general, requires fluid motion. Do not force green-on-green by excessive flight control inputs; rather, if you find yourself out of position, stabilize, and then make a positive correction back to where you want to be.

      At heavy gross weights (approaching 590K), the KC-10 becomes much less responsive and somewhat power limited. During heavy weight air refueling, a receiver pilot can help him/herself by practicing the following techniques.

      1. Insure the refueling altitude is at least 2,000 feet below the optimum altitude for end AR gross weight.

      2. Advise the tanker to allow the airspeed to build (approximately 320 KIAS) during the offload. This increase in airspeed puts the aircraft ahead of the power curve and results in fewer power changes.

      3. Avoid over-boosting the engines. Ask the pilot not flying or the flight engineer to monitor N1 settings. Direct the flight engineer to "guard" the throttle extenders and make small power reductions only if required. This allows the pilot to concentrate fully on the tanker without diverting his attention to the possibility of over-boosting engines when operating near the N1 limit.

      4. Have the PNF or FE periodically call out differences in and/or limits in N1 i.e., ""Number One - 2% below Number three,"" or ""N1 limit on Number Two.""

      5. Avoid fatigue. Pilot fatigue can pose a significant problem during heavy weight air refueling. Autopilot CWS reduces trim pressures and pilot workload. If you don’t use CWS is not used, then manual trimming by the pilot becomes essential. Holding unnecessary trim pressures for a long period of time leads to arm fatigue and loss of concentration. This has, on more than one occasion, contributed to brute force disconnects or other aircraft damage. If you find yourself working too hard and becoming tired, take a break. Get a disconnect; back out to pre-contact; and let the other pilot fly the pre-contact position. Just a short break and a couple of deep breaths does wonders for recuperating thoughts and energy.

      6. Patience, patience, and more patience is the secret to good heavyweight air refueling. Keep the aircraft inertia under control by being very patient.

      AMCPAM 10-6 1 JUN 95 5-8

      THOSE TRIANGLES

       

       

      Figure 5.-54.: Those Triangles.

       

      AMCPAM 10-6 1 JUN 95 5-9

      At night develop visual cues to supplement the director lights. If your elevation changes, your perspective of the PDI lights will change. They flatten out if high in the envelope and elongate if you are low. Some pilots form a third triangle using the KC-135’s UHF antenna or other fixed reference to form yet another triangle (See figureFigure 5.-5). Never, ever, fixate on the director lights or any one reference for more than a few seconds. Below is a list of other common visual references used by receiver pilots while in contact. Try them all and use the ones that work for you.

    1. 1. "^" formed by the UHF antenna and white line (KC-135).

      2. Position of the tanker engine pods in the windscreen.

      3. Position of gear doors on the tanker.

      4. Director light panels.

      5. Sky above the tanker wings.

      6. Centerline stripe.

      7. Lower rotating beacon.

      8. Boom pod at top of windscreen.

      9. KC-10 drain mast/VHF antenna on the nose and flap hinge on leading edge of wing.

    2. Picking up movement early and making small corrections makes maintaining position much easier. Use the PDI lights to provide trend information. Don't chase the lights, especially on a KC-10. This causes your cross-check to stagnatego to pot and pitch oscillations and wing rock inevitably result. Make small power changes. One technique is to walk the throttles up and back. Some pilots use only number two engine to make power corrections, but this doesn't work at heavier gross weights.

      Let the airplane do the work of maintaining position. The aircraft will naturally seek the area of least resistance behind the tanker which, unsurprisingly, corresponds to center of the air refueling envelope. While in this "sweet spot" the yoke will be centered if you have the airplane properly trimmed. If the yoke is not centered, then you are probably off centerline. As the receiver moves out of the "sweet spot,", (during a limit demo for example) jet wash or wing tip vortices will tend to force the outboard wing to rise. If behind another KC-10, this rolling motion can be rather pronounced. This is sometimes a hard concept for pilots to visualize. If right of centerline, don't turn the yoke left or too much bank will result and you will wind up off the tanker's left wing checking tail numbers. Avoid tail number checks by holding the wing down with aileron. By carefully releasing and reapplyingreapply aileron pressure, the pilot can walk the airplane back to centerline.

      CREW COORDINATION

      Good crew coordination is critical during receiver air refueling. The pilot flying must ensure his intentions and the status of the AR systems are known. The pilot not flying can assist by calling out distances from the boom nozzle, and inform the pilot when the aircraft is approaching a limit. The pilot flying should announce key action points and the pilot not flying should verify cockpit indications. These calls reinforce checking systems operation and the situation to preclude such things as closing without a "ready light" or backing out with contact still annunciated.

       

      Activity Pilot Flying Announces PNF Verifies PNF Announces
      Precontact "Stabilize Precontact" Zero Closure Rate, Ready Light On, Boom in Trail

      --extended 10 feet (KC-135) or 12 feet (KC-10)

       
        "Moving In" Closure Rate of Two Foot Per Second or Slower  
      Contact   Latched Light On "Contact"
      Disconnect   Disconnect Light On--Boom Clear "Disconnect"
    3. Pilot Flying Announced/Accomplishes Pilot-not-Flying Verifies

      Stabilize Precontact Ready Light On

      Contact Contact Light On

      Disconnect Disconnect Light On/Boom Clear

    4. AMCPAM 10-6 1 JUN 95 5-10

      LIMIT DEMONSTRATION

      The primary purpose of a limit demonstration exercise is to practice/demonstrate how to make controlled inputs to correct back to "center of the envelope" and to point out visual references a pilot may use to remain within the boom envelope limits. "Running the limits" builds confidence in the ability to control the aircraft and place it where you want within the envelope. This can be particularly helpful if it is necessary to use the tanker’s wing or fuselage to block out the sun and improve the pilot’s refueling visibility. In this section, some techniques will be discussed to aid in recognizing the boom limits for both the KC-10 and KC-135.

      Prior to conducting a limit demonstration, notify the boom operator and, if the tanker is a KC-135, ensure tanker disconnect capabilityWhen running the limits, it is a good idea to notify the boomer. Knowing your intentions, he can then verbalize your position to aid you in identifying visual references corresponding to the limit. In addition, a KC-135 tanker must demonstrate tanker disconnect before you accomplish a limits demonstration.

      While practicing, it is not advisable to fly to an actual limit. This is a safety precaution that also prevents inadvertent disconnects. Some pilots like to subtract one from whichever limit towards which they are maneuvering. Another technique can be referred to as the "Rule of 8.".

      The Rule of 8 adds or subtracts 8 or multiples of 8 from the center of the envelope to provide limit demo targets. If refueling from a KC-135 start at 30 degrees elevation, 0 degrees azimuth, and 12 feet extension. The practice limits are as follows:

    5. Azimuth =- 8 degrees left or right. (10° limit)

      Upper = 22 degrees (30 - 8). (20° limit)

      Lower = 344 degrees (30 + 4 [8 x 1/2]). (35° limit)

      Forward = 8 feet (6 ' limit)

      Aft =- 16 feet (8 x 2). (18 ' limit)

    6. The Rule of 8 can also be applied to the KC-10. While the actual roll limit is 25 degrees, the goal is not to show the actual limit, but is to position the aircraft where you want it and besides, it's really tough to hold 23 or 24 degrees of roll behind the Ten. This time start at 0 degrees roll 30 degrees elevation, and 14 feet extension. Be careful when refueling behind a KC-10 not to approach the limits too fast. You may be capable of stopping within the limit, but instead receive a disconnect due to the rate sensing system -- this would not have happened on the reliable KC-135.

    7. Azimuth = 22 degrees (30 - 8). (25° limit)

      Upper = 22 degrees (30 - 8). (20° limit)

      Lower = 38 degrees (30 + 8). (40° limit)

      Forward = 8 feet. (6 ' limit)

      Aft = 18 feet (21 ' limit)

    8. AMCPAM 10-6 1 JUN 95 5-11

      There are many visual references that can be used for limits, and we will not try to list them all here. Again, do not fixate on a visual reference. You are flying formation off the tanker and visual references are used as aids in flying formation. A few of the most commonly accepted KC-135 visual references (left seat) are listed below:

    9. Left Azimuth— - Just inside "Beaver Tail" on undersurface of wing. UHF antenna on edge of yellow centerline stripe.

      Right Azimuth— - Body aligned with right side of fuselage. UHF antenna near right edge of yellow centerline

      stripe.

      Upper— - White line cutting UHF antenna in half. Boom pod in top of windscreen.

      Lower— - Space equal to width of white line between UHF antenna and white line.

      Inner— - Opposite outboard engine out of view. Tanker gets MUCH BIGGER in windscreen. Boom operator is

      no longer visible (you probably wouldn’t like seeing the gestures being sent anyway).

    10. DISCONNECT

      When disconnect occurs, continue flying a stable contact position. It is imperative the pilot not flying visually confirms the boom is clear upon disconnect. Backing from contact position without the boom being clear could result in structural damage. Confirm the disconnect has actually occurred, then slowly back down and aft of the tanker. A good habit pattern to develop is to always hit the disconnect button after the disconnect. This helps to ensure a good disconnect and reinforces the action in case of a breakaway. Smooth, precision flying is as important when backing to pre-contact as it is when closing to contact. If refueling from a KC-135, little or no power reduction is required to back out. As the boom is retracted, the resultant decrease in drag causes the tanker to accelerate slightly. Conversely, when the boom is re-extended, the tanker will slow down.




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