Moving aircraft for the Luftwaffe Museum

Today’s memory missive involves a mission I flew with CW3 Ronnie Ashcraft relocating some aircraft on display at the Luftwaffe Museum in Hamburg, Germany to the new museum location in Berlin. As a result of reunification, many things were being consolidated in more central locations in Germany and the Museum was one of those consolidations. The mission was very loosely organized with three Ch-47D aircraft from A-5-159 AVN (Big Windy) sent to move some of the aircraft they had on the airfield in Hamburg to the new location. The pilots were to evaluate the aircraft and decide which could be sling loaded to the new location. Several factors were involved starting with the overall condition of the aircraft to be moved, the weight of the aircraft and how well we could rig these for sling loading. We only had authorization for a single turn so this limited the selection to three of I guess eight or ten aircraft to be moved. Several were eliminated due to weight, one of those was a soviet era cargo helicopter I estimated to weigh in excess of 30,000 lbs.

My crew and I settled on a British jet that had its engines removed but seemed to be in good shape structurally. The aviation maintenance crew set to task rigging the 110 foot slings used for aircraft recovery while my crew prepared the aircraft (Refuel, internal configuration of equipment etc.) and my co-pilot Ronnie and I filed our flight plan along with the other two crews. This was an exciting time for Ronnie, who had only recently transitioned from OH-58 Kiowa scout helicopters to CH-47Ds. Ronnie was the unit Instrument Flight Examiner (IFE) and had given me my annual instrument evaluation a few weeks earlier. Ronnie had never flown a aircraft recovery mission and so we decided that he would do the first leg of the flight to Parchim where we planned to refuel and them I would fly the second leg to Berlin. We were going as a flight of three so that we could provide support if one of the aircraft had an issue.

Once preparations were complete, we fired up our birds and we all moved into position next to our loads. The slings were laid out to the side of the load allowing you to land over the clevis and the flight engineer (FE) merely reached down and grabbed it though the cargo hook hatch and placed it on the center cargo hook. Once the FE gave up the go ahead, I had Ronnie pick us up and I explained to him how as we climbed and the slings started to get tension the pull of the load would automatically center our aircraft over the load. We then picked up the load and performed the before takeoff checks. All three aircraft tried to do this at the same time to limit the time hovering while waiting for one of the other aircraft to pick up their load. Ronnie and I were the trail aircraft and we waited for the first two birds to move out then we followed.

Since we were on the northwest side of Hamburg and we were flying southeast, the German aviation administration didn’t want us flying these loads over populated areas and had requested we fly over the Elba river through Hamburg. We flew a couple miles south to the river and then made a 130 degree or so left turn to follow the river through town. Our airspeed was limited to about 70 knots and once we were at cruising altitude, we performed our cruise check. This is when I noticed that we were picking up a forward and aft oscillation of the load. I had Ronnie make a couple of lazy left and right turns and used the lateral force of the turns to settle down the load. The problem quickly returned though when were returned to a straight flight path. I was discussing this with the flight engineer who indicated that he saw no indication that the load was causing the issue and I started to become concerned as the aircraft was starting to pitch twenty degrees nose up then twenty degrees nose down and I was worried that we might have to jettison the load.

I was discussing more maneuvers to stabilize the load with Ronnie who I noticed his thumb position on the cyclic control stick. On the right side of the grip is a button that allows you to release the force trim of the cyclic, and he was mashing it with all his might. (Force trim is a centering device that will hold the cyclic in position and is spring allowing you to move the stick against the springs and when you release the pressure, the control will return to the original position.) In small aircraft like the OH-58 Ronnie had flown for over a decade, it was standard practice to disable the trim and fly the light and nimble aircraft by the seat of your pants. In a large aircraft with a computer stabilized flight control system, this just causes the computer to fight the pilot for control of the aircraft.

I took the flight controls and the pitching of the aircraft immediately ceased and we were flying smooth and steady. I spent the next several minutes demonstrating to Ronnie where we’d been shown in the CH-47D transition. The CH-47D flies best when least interfered with by the pilot. I had pressed the Force trim button once and let go to center the pressures for the current flight profile (70 knots straight and level) and then I let go of the stick. The force trim maintained the stick position I had selected. I then demonstrated the 4-position rocker switch on top of the grip that allowed you to turn left or right, speed up or slow down all with the simple application of a thumb or finger. The collective pitch required only minimal monitoring as the weather was calm and there was little wind or thermals to cause you to deviate from altitude. Once I had the aircraft steady and had given Ronnie a lesson in the easy way to fly, I had him take to controls back and I only allowed him to use his index finger and thumb to move the cyclic and only using the 4-position switch. The flight was much smoother now letting the Advanced Flight Control system (AFCS) do all the works and Ronnie just kinda supervised.

I had really been surprised with what Ronnie had been doing as the exact way we were flying was the method most pilots used in the CH-47D to fly on instrument flights. I’d just assumed Ronnie would know that the same skills would be used on a sling load. I still struggle some times to not make assumptions, but I am learning. About the time we got things settled down, we started getting hook warning lights. The center hook on the CH-47D is rated for 26,000 lbs. and is hydraulically actuated to release. It has a hook open sensor that is activated by a plunger switch that is released when the hook is open. When released, the master caution light illuminated and the center hook open illuminates. I checked with the FE who confirmed we still had the load (I could tell by the weight but ya gotta ask) and we discussed why the light was coming an and determined that the switch was most likely out of adjustment. So aside from having to reset this errant light, no big deal.

The big deal came up as we were approaching Parchim to refuel. The FE noticed that one of the slings was fraying at the wing root on the load and that it could fail. We were fortunate to be able to get the load on the ground at Parchim, but we were end of mission at that point as we had no replacement for the sling and another aircraft would have to complete the leg from Parchim to Berlin the next day using one of the sling sets from the other two loads. Feeling a little defeated, we refueled and returned to base in Giebelstadt end of mission. It had been a good education for me as a Pilot-in-Command and I got to teach an old dog some new tricks along the way.