Relay-Version: B 2.11 6/12/87; site scolex Path: uunet!zaphod.mps.ohio-state.edu!sdd.hp.com!hplabs!hpfcso!hplvec!bills From: bills@hplvec.LVLD.HP.COM (Bill Standerfer) Newsgroups: rec.aviation Subject: KC-97 "Pilot Report" Message-ID: <2510063@hplvec.LVLD.HP.COM> Date: Tue, 12 Feb 91 11:32:59 PST Organization: Hewlett-Packard Co., Loveland, CO Lines: 193 Back by popular demand, the two year old KC-97 "pilot report". B-29 report next week... Bill In the tradition of Dan Flak, I thought I might share some big airplane information since I just happen to have the flight manual for the KC-97 Stratotanker. Unfortunately, I've never flown the beast (sigh!), but I have the real article available at the Castle Air Museum for reference. I'll post something on "my" B-29 at a later date. (yes, we crew chiefs get a little possessive about our airplanes, even at the museum.) This posting is quite long, so if you're not interested, cut out now. When I first walked up to the '97, I was impressed by its size. Not a 747, but still quite large. It is loosely derived from the Boeing B-50 and B-29 airplanes, with a much larger, double deck fuselage. The XC-97 and YC-97 were rolled out in 1948 and production ended on July 18, 1956 when the first KC-135 rolled off the line. Of the 888 C-97s built, 814 were tanker versions. A civilian version was called the 377 Stratocruiser, of which 66 were built. You enter the KC-97 through "airstair" doors, forward and aft of the left wing, to the lower deck. The lower deck on the KC-97 has fuel tanks for its inflight refueling mission while the C-97 can use the lower deck for cargo. As you enter the front door, you see the auxiliary power unit (APU) against the right wall, and a radio rack on the left wall against the forward bulkhead. The APU on this airplane is a gasoline powered generator for supplying electric power when on the ground or in emergencies in flight. From either front or rear entrance door, you can climb a six foot ladder through a hatch to the main deck. The main deck on "my" airplane has a row of basic canvas seats on the right side wall for seating 20 or so troops. The left side wall is covered with several fuel tanks (3,928 gallons total). The cargo version could be configured with 58 standard airline type seats or 96 canvas troop seats. It could also be configured for 54 litters and 8 seats for medical evacuation missions. The ceiling height is 91" in the center of the floor. There is also a winch which can be used to move cargo fore and aft on the main deck. For those long passenger flights, the C-97 had a basic galley for food preparation, and two lavatories. The right side of the fuselage has a large cargo door which can be opened for loading large items through the side to the main deck. On the cargo version, there are doors which open in the rear, underneath the fuselage for loading trucks and other cargo. This would be a great airplane to take to Oshkosh! Take your car with you! The KC-97, however, doesn't have the rear doors. Instead, that's where the refueling boom operator position is. The operator lays facing down, viewing the world through the windows in the bottom of the tail, and "flying" the refueling boom. The boom on this airplane is the modern type, much like those on the KC-135's and KC-10's. (As an aside, one of the volunteer tour guides at the museum was on a crew for a short time in the very late 1940's which did some of the first midair refueling from a converted KB-29 tanker. The refueling "boom" was a large reel of hose, unwound from the bottom of the KB-29. The other airplane would have someone onboard actually grab the hose, pull the end inside, and make the connection for fuel transfer. After the job was done, the hose was reeled back into the KB-29 by a couple of crewmembers. There was a guillotine to cut the hose in case of trouble. This guy survived the duty long enough to finally move up to flight crew and later commanded KC-97's and KC-135's.) At the front of the main deck, a step up puts you on the flight deck, the front office with a staff of four. As you enter, on your left, is the radio/radar operator. In the center is the flight engineer's chair, with his panel to his right. Around the right side, behind the engineer's panel, you can walk to get to the copilot's position. Around the left side and you get to the aircraft commander's seat. Let's take the AC's seat for a moment. As you sit down, you'll notice the nice view from the front. This airplane has so many windows in the nose that it looks like a microscope picture of the eye of an insect. Still, you have to move forward a bit to see the left wing and engines. The flight controls are driven by the old style wheel type yoke, but they are not boosted with hydraulic assist. The rudder does have some assist available, however. The panel layout is almost what you would expect in layout, but still has that cut and paste look for some things. The '97 has power steering, controlled by a separate wheel ahead and to the left of the AC's left knee. Hanging down from the roof, between the AC and copilot is a long tube which houses a search radar display. This is from the days before digital memory. The only memory for the display was the persistence of the orange phosphor in the CRT. Between the AC and copilot is the isle stand with throttles, trim wheels, radio control heads, etc. On the KC-97L model airplanes, there are two additional throttles to the right of the standard throttles to control the two jet engines (see later). The four main throttles work normally for idle through full power. Pulling the throttles up 1/4" and past the idle stop gets reverse propeller pitch for short field landings. At the rear of the isle stand, in front of the engineer as he faces forward, are additional throttle levers (connected to the pilot's set), mixture levers, and prop pitch switches. To the left of that is the engine analyzer oscilloscope for fine tuning and diagnosing the monster radials. Overhead, accessible primarily by the engineer are more switches, breakers, etc. The four magneto switches are on the overhead panel over the flight engineer. Directly in front of him in the overhead panel are the fire control switches for getting the engine caged and fire retardant going quickly. The engineer can swivel his chair to the right to face the main engineer's panel. On this panel are located most of the engine instruments, fuel controls, pressurization controls, etc. To the right of the engineer's main panel, against the cockpit rear bulkhead, is an additional radio rack. Behind the engineer, on the left side of the rear flight deck, is the radio/radar operator's position. He has instruments for navigation, additional radio control heads, radio compass controls, and the SCR-718C radar altimeter controls. He also runs the APN-70 LORAN system. This is not your basic II Morrow LORAN. It is a very complicated, very manual LORAN receiver that would use up most of the payload of the average GA airplane. I suspect the modern units of today are more accurate at a very small fraction of the cost. So much for the interior tour. Let's take a look outside. Back down the ladder to the lower deck and out the front door. The engines are Pratt and Whitney R4360-59B 28 cylinder turbosupercharged engines. Each produces up to 3250 HP dry or 3500 HP if you inject a little water-alcohol mixture into the carburetor. There's a 10 minute supply of water (two 30 gallon tanks) for takeoff. The four propellers are Hamilton Standard four bladed types with diameters of about 18 feet (yes, Virginia, that's 18 feet!). I don't have the exact dimensions, but that's pretty close. In 1965, the Hayes Aircraft Company began modifying Air National Guard KC-97's by adding a jet engine hung on each wing outboard of the outboard radial engines. The version was designated the KC-97L and allowed increased gross weights at takeoff and better speeds for refueling jet fighters. The engines are GE J-47-25 turbojets producing 4,000 pounds of thrust. Wing span is 141' 3" and length is 110' 4" without the refueling boom. It is 38' 3" to the top of the vertical stabilizer. C-97 gross takeoff weight is 153,000 pounds for 2.5G loads or 169,000 pounds for emergencies, but limited to 2.25G loads. Normal maximum landing weight is 130,000 pounds. The L model airplanes with the jets have a 175,000 pound gross weight. Total usable fuel for the C-97 is 46,740 pounds (7790 gallons), loaded through ports in the top of the wings, just like your Cherokee or 172. There is also a provision for single point pressure fueling through a port on the left side of the fuselage, just under the wing trailing edge. Fuel grade is the best 115/145 hi test your local Texaco dealer can offer. No mogas STC for this one! The tanker carries an additional 5,828 gallons extra for inflight refueling, which it can pump out at about 600 gallons per minute. With all the discussions lately on the net about icing, let's look at the KC-97 de-ice system. There is a large gasoline fired heater in each outboard engine nacelle, and one in the vertical stabilizer. These feed hot air through corrugated pathways in the leading edges of the wings and tail surfaces. Air is taken through large intakes in the wings just outboard of the outboard engines. After heating the wings, hot air is expended overboard through ports under the wings and tail surfaces. The wing heaters can also be used to preheat the engines on the ground by using large flexible ducts to pipe the hot air to the cowlings. Each propeller blade is de-iced with electrically heated boots. Several of the cockpit windows are heated with integral heating elements. Speeds in the KC-97 are not impressive by today's standards. Cruise speeds are in the 220 to 240 knot TAS range, heavily dependent on weight, at 25,000' (a little faster for the L model). It'll outrun a Malibu, but not by much. Range is in the 2,000 to 3,000 NM area for the cargo airplane, again depending on weight. For long ferry flights, you can use all the fuel in the tanker version for it's own engines, upping the range to around 4,500 NM (make sure you've purged the extra tanks of JP-4 before filling with AVGas!). Of course, that all depends on all engines running. There are charts in the C-97 flight manual for three and two engine cruise. Just in case. Fuel flow is in the 100 to 150 GPH range (EACH engine) at cruise, depending on how good your engineer is at leaning. Takeoff runway requirements are in the 6,000 to 7,000' range for accelerate-go distance, at 150,000 pounds. Takeoff speed (Vr is not specified) is around 110 KIAS for 55% flaps and 120 KIAS for 33% flaps. Takeoff speed is when the main wheels leave the ground. There are charts in the C-97 flight manual for three engine takeoffs in case of emergency evacuation. Not for the faint of heart! Climb is not, shall we say, spirited. Even at METO power (absolute maximum), rate of climb is between 500 and 1000 FPM. Of course, you pay for all that performance. Now you are drinking fuel at the rate of 130 pounds per MINUTE. That's 325 GPH per engine. Better have your Visa card handy when you land. Landing speeds are not too bad, either. For example, at 120,000 pounds, threshold speed should be 113 KIAS with 100% flaps. Ground roll is less than 3,000' using just brakes. With reverse thrust, the ground roll is just a tad over 1,500'. Hey, we could get this thing into Harris Ranch! Well, that's enough of a cook's tour for today. I'll be glad to attempt to answer any specific questions anyone has on the bird. Let me know if this is the sort of thing the net is interested in. There is enough research material (and real airplanes) at the museum to do several more from time to time (B-29? B-50? Buff? etc.). Sort of a pilot's report without flying, I guess. Bill Bill Standerfer -- KF0DJ -- Baron N1746W bills@hpisla.hp.com or {...}!hplabs!hpisla!bills Hewlett Packard Measurement Systems Operation PO Box 301, Loveland, CO 80539 -- 303-679-2378