54th S&B Abstracts
Robert L. Cardenas
Brig Gen, USAF (Ret)
Brigadier General Robert L. “Bob” Cardenas, USAF (retired) Test Pilot, Combat Leader in both Bombers and Fighters as well as Commander of the Air Force Special Operations Force. He has flown over 60 different aircraft in his career.
General Cardenas began his military career as a Private in the Army Cost Artillery, before joining the Army Air Corps. He was commissioned a 2nd Lt. in July 1941 and in 1942 was sent to 29 Palms, CA to establish an Army Air Corps Glider School.
In 1944 he flew combat missions in B-24 Liberators in the skies over Germany. He was shot down on his 20th mission but was not captured. He escaped into Switzerland and then into France prior to D Day. He was later flown back to England and to a rehabilitation center in the US. He became a test pilot after his graduation in 1945 from the Flight Performance School at Vandalia, Ohio.
He participated in the flight test evaluation of the German jet fighter ME-262 and the Arado 234 bomber. In 1947 Cardenas was a key member of the X-1 supersonic project. Major Cardenas was the Officer In Charge Of Operations and command pilot of the B-29 that launched Captain Charles Yeager into the realm of supersonic flight.
In 1948, he was assigned as Officer in charge of Flight Test Division projects at Muroc AB and as Chief Air Force test pilot on the YB-49 flying wing project. After completion of the Performance Phase II tests he checked out Captain Glen Edwards in the YB-49 on May 20 and 21st. He then received orders to USC for completion of his Aeronautical Engineering degree. He was ordered back 15 days later, after the crash of the YB-49 and loss of the crew, in order to complete the Stability and Control Phase in the remaining YB-49 aircraft. In January 1949 he was ordered to fly the YB-49 from Muroc AB to Andrews AFB in Washington for President Truman’s Air Show. The transcontinental non-stop flight set a record time of 4 hours and 5 minutes.
During the Korean War, Cardenas was at Wright Field and Edwards AFB testing new jet fighters and bombers and following Air War College served as Commander of the 51st Fighter Interceptor Wing at Naha AB on Okinawa, followed by tours at the Pentagon and US Strike Command. In 1962 he led a joint Army and Air Force Special Force into the Kashmir, India for the purpose of evaluating and improving high altitude resupply drops in the Himalayan Mountains. He used these techniques to equip forces and prevented an incursion of Chinese through the Himalayas linking into East Pakistan.
He was then sent back to Okinawa as Commander of the 18th Tactical Fighter Wing at Kadena AFB. After the Gulf of Tonkin crisis he flew F-105 combat missions from Korat, Thailand over North Vietnam. He returned to the US to command the 835th Air Division at McConnell AFB, training F-105 crews for combat in Vietnam.
He was promoted to Brigadier General in 1968 and placed in command of the Air Force Special Operations Force at Eglin and Hurlburt AFB, Florida. On October 12, 2002 his contributions to the development of Special Forces was recognized by induction into the Air Commando Hall of Fame. Further prestigious assignments followed, and as Vice Commander of the 16th Air Force in Spain he had the dubious honor of negotiating with Muammar Gadhafi the withdrawal of US forces from Wheelus AFB in Libya. General Cardenas retired in June 1973.
Cardenas has been honored by the Distinguished Service Medal, Legion of Merit with Oak Leaf Cluster, Distinguished Flying Cross, Purple Heart, Meritorious Service Medal, Air Medal with four Oak Leaf Clusters, Joint Service Commendation Medal, Air Force Commendation Medal with Oak Leaf Cluster and the Presidential Citation. Foreign decorations include the Spanish Grand Legion of Aeronautical Merit with Sash and Dagger.
Since his retirement, General Cardenas has held a number of prestigious positions, including his appointment in 1983 to the White House as the California coordinator for President Reagan’s Southwest Boarder Economic Action Group. Other appointments include being Chairman of the Juvenile Justice and Delinquency Prevention Advisory Group, a member of the California Council of Criminal Justice, Chairman of the California Veterans Board, Chairman of the San Diego United Veterans Council, and Director on the Board of the Veterans Memorial Center and Museum. He was recently appointed by the VA Secretary Anthony Principi to the VA Memorials and Cemetery Committee in Washington.
He has been honored by the University of New Mexico for outstanding professional contributions, the USAF Test Pilot School as distinguished alumnus and on September 1995 he was inducted into the “Aerospace Walk of Honor” at Lancaster, California. The Sigma Chi fraternity celebrated 150 years of existence in 1995, selecting 150 of their members for the “Significant Sigma Chi Hall of Fame" and including General Cardenas, who says he was extremely humbled to have been chosen, and more so when he saw who the other 149 were.
General Cardenas lives at home with his wife Gladys and their children and grandchildren in San Diego, California.
RAPID DEVELOPMENT OF THE X-55A AND INITIAL
FLIGHT TEST RESULTS
Robert A. Rowe (AF), Lockheed Martin
Even before the ACCA program was initiated, Lockheed Advanced Development Programs [ADP] was doing studies under another contract to look at the overall feasibility of building a large composite aircraft about the size of a C-27. These estimates showed it would take about 3 years and over $150M to execute. When the actual RFP from the Air Force Research Lab [AFRL] came out for ACCA at a cost of $50M and less than 18 months to complete, you can imagine there was a lot of headshaking and discussions about what, if anything could be built that quickly and for $50M dollars that would still meet the overall requirements of a large cargo aircraft. This is when an idea, some would say a crazy idea came about: This idea was to utilize an existing aircraft, namely a Do-328J and chop off the flight station, wing and horizontal tail to re-use on a brand new composite fuselage and vertical tail came about.
This program would not have started correctly had we not put together such a phenomenal proposal and program plan. People like Steve Justice, Scott Burleson, Jeff Cramer, Ken Gousman, John Carter, and many others helped construct a plan that gave us a way to absorb schedule impacts due to unforeseen issues that may arise, which turned out to be exactly what happened.
We were awarded a Phase 1 contract in April 2007 to do preliminary design and risk reduction tasks in support of the Phase 2 effort to actually build the aircraft. During the course of this initial 5 month Phase, the team had to become experts in the Dornier 328, even though it’s not made by Lockheed Martin. This presented many challenges and without being able to obtain the original technical data on the aircraft or the assistance of AvCraft, who maintains Do-328’s. We would have fallen way behind in the design effort right from the start without them. People like Kevin Kelly, Derek Paige, Daren Kimura, Steve Burns, and Guy Rossi led the technical effort successfully through Phase 1 and were critical to us winning the Phase 2 contract [from AFRL] to build and fly the aircraft.
In October, 2007 we were awarded Phase 2 which was the actual build of the demonstrator. The single biggest challenge at that time was the fact that we were developing new material processes and manufacturing methods at the same time we were building the aircraft. It was up to folks like Brian Shoemaker, Steve Laveaux Craig Smith, and Tony Borgia to lead the production operations, and advanced prototyping center efforts to build aircraft structure with materials and processes that had to be developed on the fly. In some ways, I think it was similar to what the team developing the SR-71 had to go through when they started using Titanium to build airframes. We had a pretty high scrap rate initially and were conducting hundreds of coupon tests to better characterize the structural performance of the materials. In the end, we were able to overcome these obstacles and get to the point where we were able to produce a composite airframe that passed all of structural tests and airworthiness certification process.
Finally it was actually time to test the aircraft that we built under the leadership of Jim Harris, our pilots Rob Rowe and Joe Biviano and the rest of the safety and flight test team. We conducted a series of system checks on the aircraft, engine ground runs, and a series of taxi runs before taking to the air on June 2nd. We flew for 1 hour, 29 minutes, achieved a maximum altitude of 12,000 ft. and a maximum speed of 162 kts. We completed all 29 of our planned test points and brought the pilots and aircraft safely home.
Our AFRL Customer has been elated with the program outcome and has said that the ACCA team was the finest team he has had the privilege to work with.
Interestingly for AFRL, ACCA is the first, new mold-line, manned technology demonstrator aircraft that the Air Vehicles’ Directorate has produced in over 20 years (the previous being the STOL F-15 in 1988). As such, it represents the revival of a heritage that dates back to the formation of what is now known as AFRL.
In sum, AFRL met 4 of their 5 technical objectives:
- We accomplished accurate, detail design of the aircraft concept in 5 months using advanced analysis methods
- We advanced the state-of-the-art in composite materials technology by utilizing a material blend (MTM-45) on the largest (known) physical scale is the aerospace industry
- We advanced the state-of-the-art in manufacturing technology by successfully applying out-of autoclave curing at the largest (known) physical scale in the aerospace industry
- From a “standing start”, we fabricated, certified and flew the aircraft in 20 months versus the 12 month goal
- We were able to complete the project within the $50M limit set for government investment. Key cost-saving features were order-of-magnitude reductions in both part count and mechanical fasteners relative to the metallic baseline. The compounding effect of these features enabled us to absorb an 8-month schedule slip and stay within budget, serving as testimony to the power of composites technology.
The road to first flight started over a decade ago with industry and government laboratories collaborating in the AFRL-Led Composites Affordability Initiative (CAI), a series of critical development steps in both materials and manufacturing technologies designed to mature dramatic, cost-saving processes. Out-of-autoclave curing of large, unitized and co-bonded structures minimizes part count and mechanical fasteners. The “ripple effect” of this approach spreads across every aspect of airframe production expense. Tooling, raw material, fabrication man-hours, quality control and floor space utilization efficiency are just a few of the factors that combine to create a compounding effect on cost when applied in a holistic manner. ACCA is the “capstone” test of integrating these CAI principles all the way from conceptual design through certification and flight. Despite its larger size, the materials and processes used for the fuselage reduced the number of parts by an order of magnitude relative to the original metallic design (approx 300 vs 3000) and drastically reduced the number of mechanical fasteners (approx 4000 vs 30000). 
Flight Test of the Boeing 737 Airborne Early Warning and
Control Countermeasures Dispense Envelope
Norman E. Howell (AF)
The Boeing Company
The Airborne Early Warning and Control (AEW&C) aircraft, based upon the Boeing Business Jet 737-700IGW model with CFM56-7B27A engines and auxiliary fuel tanks, is the airborne mission segment sold in direct commercial sale to provide modern surveillance, command and control capabilities for international air, land and sea forces. The AEW&C aircraft hosts a multimode
EVALUATION OF ASYMMETRICAL ROLL RATES OF THE HH-60G
Lt Col Paul Fiorenza, USAF
Maj Jeffery Mabry, USAF (M)
Over the last decade USAF Combat Search and Rescue helicopter pilots have increased operations in high density altitude, heavy weight conditions during ongoing conflict in South West Asia. While executing combat maneuvers in this environment operational pilots have noted under certain conditions in a right-hand turn that the helicopter does not appear to roll out of the turn at the expected roll rate. Pilots have occasionally reported hitting the left control stop while trying to roll out of steeply banked right-hand turns. This phenomenon has been reported to be repeatable, primarily during high gross weight, high angle of bank (AOB) turns. Furthermore, between 2000 and 2008 two “Class A” mishaps occurred during low altitude maneuvering flight in good weather conditions. In both cases the pilot failed to recover from a steep banked right turn.
In 2007, Det 1, 413 Flight Test Squadron, Nellis AFB, NV began an evaluation of HH-60G lateral flying qualities to support a simulator data collection effort, in partnership with the Army Aviation Test Center, Ft Rucker, Al. The purpose of the test was to investigate the roll rate characteristics of the HH-60G in forward flight. The flight test was designed to quantify roll rates of the helicopter and determine procedural and/or material solutions based on the data collected. Additionally, testing was designed to determine and isolate the variables that contribute to a suspected reduced left roll rate. The test sequence explored AOB, collective power position, airspeed, control input combinations, magnitude of lateral control input, and recovery techniques.
Follow on data analysis in 2008 and 2009 identified significant asymmetrical roll rates in forward flight. When attempting left rolls to recover from high load factor right turns, it was demonstrated that steady state roll rates were only 50% (20 deg/sec vs 40 deg/sec) of those recorded when executing right roll recovering from left hand turns. A clear correlation existed between increased load factor and the reduced left roll rate due to a load factor induced right rolling moment. This right rolling tendency resulted in a left lateral cyclic stick migration to achieve stabilized right bank turns. The rolling moment was assessed to be the result of changes in lift across the rotor disk under loaded flight, creating a “coning roll” to the right. The combination of lateral stick migration to achieve balanced flight and a reduced left cyclic envelope at high collective settings resulted in a reduction in control envelope available to recover from steep bank right hand turns. Collective reduction of approximately 20 to 40%, or 2 to 3 inches, was demonstrated to reduce the load on the aircraft sufficient to regain left roll response; however, this technique resulted in significant increase in altitude lost.
The proposed presentation will discuss Power Point slides comparing lateral flying quality time histories under varying airspeed and load factor flight conditions. Test pilot narration of composite test video and data recording will also be presented. Following data presentation, an analysis of the multiple factors leading to the observed roll rate asymmetry will be discussed, including flight control design, tail rotor influence, sideslip, loadfactor effect on control power, and aerodynamic influences on the helicopter’s blades including blade stall, non uniform inflow and coning roll. The presentation concludes by illustrating how undesirable handling qualities of multiple design and aerodynamic factors conspire to result in a situation where a transient negative stability condition can be achieved while executing maneuvering within flight manual limitations.