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Flying Proteus

An afternoon with Mike Melvill

By Marc J. Zeitlin, EAA 475937, marc_zeitlin@alum.mit.edu

Proteus
A Proteus aircraft flies over Southern California, September 30, 2006, carrying the Global Hawk variant of the Multi-Platform Radar Technology Insertion Program radar. Proteus is a high-altitude aircraft similar in size to Global Hawk.  (U.S. Air Force photo)

Having had one opportunity to fly as the flight test engineer (FTE) in the third seat on WK2 a few weeks ago, I was afforded the opportunity to fly on Proteus in the right seat as FTE last Tuesday. Proteus has been flying for about 12 years and is currently carrying a large pod, doing proprietary experiments for a customer. No, I won’t tell you who it is, and the accompanying photo is merely an example of pod carrying.

By the way, if you’re interested in performing high-altitude experiments, there’s no cheaper way to get up high with a payload – give Scaled Composites a call with your proposal (wink). Anyway, since Proteus is a canard aircraft, I thought that it might interest people to hear the following flight report.

Mike Melvill was assigned pilot in command in the left seat for the flight I was on, so I had the privilege of flying with him. Although Mike is retired from Scaled, he still does a substantial amount of contract flying. My job as FTE was to read the checklists for the flight, monitor the experiment, run the three laptops we had in the cockpit – one for Scaled to help with navigation (along with the two Garmin 430Ws) and two for the customer’s needs and generally to do whatever Mike told me. I spent a few hours the day before becoming conversant with the 430s and the flight plan. I also spent a few hours with Mike discussing the aircraft (which has logged over 1,500 hours, if I recall correctly), its flight characteristics, the course of a flight, and how to manage the experiment.

The morning of the flight, the customer briefed us on the mission plan. We then suited up and the ground crew got the plane ready. Although Proteus has over 3,000 flight hours (it was built as a proof-of-concept demonstrator, but it’s amazing what good maintenance can achieve), the crew still wears fireproof flight suits and parachutes on every flight, and not the lightweight glider type, either. The cockpit is reasonably sized for a crew of two, but the rear of the cockpit is crammed with the customer’s equipment, flight control bits, bleed-air outlets, and more cabling than you can shake a stick at. Getting in and out takes some practice, using a handrail on the roof and hanging to get your feet into the footwells. Proteus has sidesticks, just like a Cozy, and a four-point harness restrains each crew member.

The instrument panel is old-school – no glass screens other than the 430s. There’s an inertial navigation system (INS) feeding a homegrown flight management system (FMS) and a homegrown autopilot that takes its feed from the INS. The autopilot is, to say the least, idiosyncratic; it took Mike and me a while to figure out how to get altitude hold to work.

Getting Ready to Launch
The preflight in-cockpit checklist takes about 15 minutes to get both the plane and the experiment ready for taxi. After engine start, we taxied out to a pad at the end of the runway and spent the next 75 minutes (with the engines running) getting the aircraft and the experiment ready for flight – there are numerous checklists to run through with ground, maintenance and control booth crews. It gets pretty hot sitting on the ground in Mojave at noon With the engines at idle, the air conditioning is pretty anemic. At least we didn’t have helmets and masks on. Just headsets, with O2 masks close by for emergencies. At last, everything was ready for flight.

Mike taxied out, advanced the throttles, and we took off at speeds not too much higher than Long-EZ/Cozy drivers would be used to. Rotation was about 90 knots and climb at about 100. Climb speed, fully loaded, was about 1,500 feet per minute. In this case (as with many commercial flights), fully loaded means above the maximum landing weight. Without a fuel dump system, we’d have to fly around for an hour or two to burn fuel if the mission got scrubbed early before we could land.

The Climb
At any rate, we continued a climb up to the low 40,000-foot range, coordinating our climb with Joshua approach and Los Angeles Center. We saw one F-15 below us as we climbed, and then a commercial airliner heading into Las Vegas later in the flight. They were the only two aircraft we saw in the four-hour flight. After entering LA Center’s airspace, we continued the climb and leveled out well above any commercial flight altitude, and higher than that of just about all bizjets as well.

During the climb, I had to modify the Excel spreadsheet that we were using to assist our navigation since there were a few omissions in it. But by the time we reached our first waypoint, we were ready to go.

For some reason, the winds reported by the FMS (working off the INS) and those reported by the Garmin 430 were reasonably different – maybe by 40 degrees and 20 knots. After some head scratching, I decided to average the two and use that value for our navigation. A few legs of data gathering passed, and we had determined a rhythm for wind measurement, leg flying, and transitions. We were able to hold heading and position within 0.01 nautical mile and 1.5 degrees, so we were happy.

The Descent
After about three to four hours of data gathering, sightseeing, and looking down on the Mojave Desert (and everything within about 200 to 300 miles, given our altitude), we finished up and headed back. Mike let me fly the descent. Proteus has no drag devices – no flaps, no speed brakes, no air brakes, no landing brake – and a maximum g-loading of two in its current configuration, so descents are slow, with a rate of 1,500 feet per minute at about 130 knots indicated. From way up high, it takes a long time to get down.

While Mike had led me to believe that Proteus was somewhat similar to other canards in its flying qualities, I’d say that it’s more like driving an 18-wheeler that’s had its power steering and power brakes fail. The stick forces are immense, and the plane’s response is relatively slow. This is good because of what the plane was designed for – a stable platform for telecommunications. For whizzing around the sky, however, forearms like Popeye’s would be useful. I was able to keep the plane within about 5 knots of our intended airspeed and within the appropriate airspace as we descended. Mike seemed pleased with my flying.

As an aside, after the data gathering and during the long descent, there’s a lot of time for yakking. Mike thanked me for giving him a ride in my Cozy at the Kanab fly-in, and I expressed surprise that with Cozy being around for over 25years that he’d never had a ride in one before. He said he didn’t like to ask folks for rides in planes, as he didn’t want to trade on his “fame” and make folks feel obligated to give him a ride if they didn’t really want to or feel comfortable doing so. I told him that I knew hundreds of canard flyers, and I couldn’t think of one that wouldn’t be thrilled to give him a ride if he asked. So, if you see Mike and he’s eyeing your plane, offer him a ride. He won’t ask for it.

At any rate, I managed to avoid the fire temporary flight restriction over Bodfish, California (a huge fire that was spreading smoke over the Lake Isabella region, with winds carrying the smoke over the Sierras, the Owens Valley, Panamint Valley, and Death Valley), overfly Tehachapi, stay in the required airspace, and get us down and near Mojave. We discussed the winds, which had picked up, and after some quick crosswind calculations, determined that we should land on two-six. I got us onto downwind and Mike got us on the ground. Landing speeds were also not too dissimilar to Long-EZ/Cozy airspeeds – 90 knots or so in the pattern and maybe 85 knots at main gear touchdown.

Proteus

Since Proteus was originally designed to carry a huge circular dish under the fuselage, the main landing gear is about 6 feet aft of the normal center of gravity (CG) positions. Because of this, at normal flight CGs it’s almost impossible to hold the nose gear off the ground with elevator after main gear touchdown, and the nose gear slaps down pretty hard. Not “break things” hard, but hard enough that you’d be upset at the commercial airline pilot who let the nose down  at that magnitude. We were able to turn off two-six at the Echo taxiway and taxi back to the hangar.

Down Safely
Following a few minutes of cool-down, we shut down the engines and aircraft, and the ground crew pulled the plane back into the hangar. We deplaned and held an informal debrief with the Scaled engineer responsible for the aircraft; the customer had long since finished his debrief of the flight.

After stealing some leftovers of KFC that the customer had ordered for his folks, I thanked Mike for the experience and headed home. Mike said next time (whenever that might be) he might let me try a takeoff and landing. We’ll see…

 
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