Archive for Boeing

Jet Fuelishness

Posted in air travel, airline pilot blog, airliner, airlines, airport, flight crew, jet, passenger, pilot, travel with tags , , , , , , , , , , , , , , on November 15, 2013 by Chris Manno

I’ve always agreed with the pilot maxim, “The only time you can have too much fuel is when you’re on fire.” But, as with all things in life, there’s a catch: first, you have to be able to lift the weight into the air, and second, you have to be able to bring the tonnage to a stop on landing.

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Two simple requirements, or so it would seem–yet nothing could be further from the truth. Let’s look at the second requirement: stopping distance.

All month I’ve been flying into John Wayne-Orange County Airport in Santa Ana. That’s by choice–I like the  typically favorable weather, plus the lack of ground traffic that makes for a quick in and out. Plus, the food options from Gerry’s Wood Fired Dogs to Ruby’s awesome turkey burgers rival the Udon, Cat Cora and Tyler Florence options at San Francisco International. But I digress.

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Today I’m flying the 737-800 from DFW to Santa Ana (SNA) and approximately 2 hours from takeoff, I’ll call Flight Dispatch and ask, “What fuel load are you planning today?” And he will say, “I don’t know.”

That’s because the flight planning system won’t issue a fuel load until one hour prior. I realize that–but as crew, we show up one hour prior and by then, the fuel is already being pumped into the jet. I want to shortstop a problem unique to SNA. That is, fuel is really expensive at some California airports, including taxes, airport assessments and surcharges. So it does make sense to “ferry” some fuel into those airports.

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That is, if I need an arrival fuel of say, typically, 5,200 pounds in order to have divert or go-around options at the destination, we fuel up to that total, then add “ferry fuel,” or an additional upload so as to require less refueling, buying less with the added fees, taxes and cost for the return flight.

Problem is, SNA has a fairly short runway (5,700 feet, versus 13,000 at DFW) making stopping distance is critical.

So, while extra fuel saves money on refueling (yes, you have to figure that it does exact a higher fuel burn inbound because of the additional weight), we still have to have a sufficient stopping margin.

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In all cases, the maximum landing weight of the jet based on the structural limit is 144,000 pounds which, on a dry runway, requires 5,300 feet out of the 5,700 feet available to stop. I discount headwinds, which are favorable, and simply disallow tailwind corrections: at 144,000 pounds, I require zero–I’m not even trifling with a 400 foot margin touching down at 150 knots.

So my effort in calling Dispatch is to intervene in the numbers game: do NOT plan max “savings” ferry fuel until you know what the zero fuel weight (passengers, cargo, empty jet–everything BUT fuel) is.

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Then subtract the zero fuel weight from 144,000 (max landing weight), deduct the planned enroute fuel burn and see what is left over–THAT , minus 2,000 pounds as a safety buffer (mine personally), and you’ll have a reasonable ferry fuel load.

The problem is, by the time I get to the jet, the “planned” fuel load–which doesn’t include the above calculation, because the zero fuel weight isn’t firm yet–is already aboard. If I do the math and find that we’ll be arriving weighing over the max landing weight, I have two choices: defuel (bad choice) before pushback or fly lower (dumb choice) to reduce the landing weight.

Both are bad options: if we defuel, that fuel must be discarded–trashed–because quality assurance standards wisely say you cannot take fuel from one aircraft’s tanks and meet the purity standards for another aircraft. So that’s money in the trash, plus a guaranteed delay to accomplish the defuel.

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The “fly lower” option works, but look what we’ve done: to “save” on return fuel, we’ve wasted thousands by flying at 24,000 feet versus 38,000 or 40,000 feet, just to squeak in under the maximum landing weight. And it’s bumpier and noisier down there among the cumulus clouds.

I always choose the second option, although I don’t always like landing at the maximum structural limit of the airframe on the shortest runway in the system. But, at least we can save the absolute maximum fuel for the return, rather than simply defueling into the trash.

On a longer runway, say LAX, stopping distance wouldn’t be a consideration, but the 144,000 pound limit is simply universal: doesn’t matter where you land, 144,000 pounds is max allowable. I need to intervene in the mathematics before the fuel goes on the jet outbound.

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The second, problem: the return. Dispatch may shave the arrival fuel to 5.0, which is sufficient, but there’s a catch. He’s planned us at a low altitude (29,000) because of chop reported in Arizona at the higher altitudes. If he’s right, at that lower altitude (FL290) I know from 38 years as a pilot that there will be both flight deviations for spacing or weather, or a choppy ride anyway.

So here’s what I personally do: I add another thousand for additional time and distance flexibility in case the turbulence forecast is correct–but I also plan to climb immediately to 39,000 feet to see for myself if the ride is choppy. That’s because I’ve just flown through that airspace inbound and know firsthand what the winds and the rides are, whereas the Dispatch and even the ATC reports are hours old. Plus, and again, this is based on over 22 years as an airline captain, I know we’re taking off at dusk and the entire thermodynamics of the air mass will change dramatically.

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So based on intuition, I’ll do the climb to 39,000 and “take the hit:” the early climb will be heavier and burn more fuel versus a later step climb, but my gut feel says we’ll regain that amount and more by cruising the longer time at the higher altitude. Notice I didn’t say 41,000, because I’m claiming a little pad because of the narrower range between high and low speed buffet at the max altitude. Plus, this time of year, surfing the jet stream at the higher altitudes will get you 510 knots or more across the ground. That’s the pay dirt of efficient flying.

Also, if I’m wrong, I did add the fuel pad up front. But I bet I’m not. The alternative is to fly lower (noisier, crowded, more weather) and experiment with the step climb–which burns fuel, too, and if you have to come back down because the ride’s bad, you’ll wish you hadn’t. But in the worst case, we’ll still land at DFW with a comfortable fuel pad.

And if I’m right, we’ll save a couple thousand pounds eastbound at the higher altitude and land fat on fuel. Fuel is time, to me, so nothing could be more important than more fuel.

Unless as I noted above, you’re on fire, or more realistically, as I’ve just explained, you’re trying to achieve the best outcome as efficiently as possible. Anything less is just plane fuelishness.

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Flight Crew Talk: The Beatings Will Continue.

Posted in airline cartoon, airline pilot blog, flight, flight attendant, flight crew, jet flight, travel with tags , , , , , , , , , on May 15, 2013 by Chris Manno

What we have here . . . is a failure to communicate.

You wouldn’t think it would be so hard for crewmembers to communicate in flight–we have the technology; interphone, PA system, headsets and handsets–even our oxygen masks on the flight deck are wired for sound.

Nonetheless, once the cockpit door is closed, communication dies a slow, miserable death and as captain–it’s YOU taking the Cool Hand Luke beating from the Road Boss.

You don’t like it, I don’t like it–but that’s the way he wants it . . . so he gets it.

Let’s start with what’s usually the first salvo, fired right as we climb through ten thousand feet. That’s the magic end of “sterile cockpit,” which is the time period when flight attendants know non-essential communications with the pilots is prohibited because it’s a phase of flight requiring our concentration in the cockpit, and distractions are not welcome. I have answered the crew interphone when we’ve received a call below 10,000 feet with the admonishment, “We’d better be on fire if you’re calling me now.”

But above ten thousand, here it comes: “Can you turn down the air?”

Sigh. What does that even mean? More cold air? More hot air? Higher temperature? Turn down? So begins twenty questions: “What is it you want?” Sadly, though, the whole thing is our own fault or, honestly, usually the F/O’s fault.

ac tempThat’s because F/Os just CANNOT LEAVE THE TEMP CONTROLS ALONE. This is especially true of those with lingering brain damage from the MD-80, which essentially had a caveman vintage air conditioning system that DID require a lot of tweaking. On take-off, at full power, it could make snow in the back if you didn’t nudge the temp control valve off of the full-cold stop.

Not so with the Boeing–but F/Os HAVE to mess with it anyway–even though if the temp was comfortable on the ground, the Boeing will maintain that in flight.Nope–F/Os have to mess with it, have to do something, even though automatically, it’s fine left alone.

And that brings on the second failure to communicate. Inevitably, the F/O has to argue, usually tossing out, “Well, the duct temp says 75 degrees.”

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Unfortunately, the crew interphone system is a party line, and the flight attendants are listening. Sigh. They don’t give a damn about the duct temp–neither do I–they just know if they’re comfortable.  But that’s the pilot pigheadedness: we already know everything.

To reiterate, as I bump all three compartment temps down, just leave it alone, and give them whatever the hell they want. What do you care? You’re not back there.

Plus, use your head: this is a senior turnaround flight, with senior flight attendants swathed in layers of polyester, hauling carts and traipsing up and down the aisle. You think they want heat? You think I do? Sitting in the gazebo, direct sunlight–I constantly reach over and call for more cool air. You’re cold? Too bad–next flight, bring a sweater.

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Now, let’s visit the cruise portion of our non-communication. The primary voice passengers hear is the PA, which announces information pertinent to our flight, like arrival time and weather. That’s key information for travelers and crew alike. But, there’s a catch: flight attendants can’t hear the PA.

For flight attendants, the PA is like a dog whistle: we can all hear it, average dogs that we are, but flight attendants are oblivious. You could have just said over the PA “we’ll be landing in one hour” and within minutes, the interphone chime will go off and the question will be, “When are we landing?” And not just once, because not only do flight attendants not hear the PA, they don’t talk to each other either. So you’ll get the same call two, maybe three times.

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And never mind that you’ve given them a hard copy of the flight time before takeoff, and that they’ve typed that information into the touch screen at their station controlling the passenger information and entertainment system . . .

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. . . and that touchscreen, if they look at it, will tell them how much longer we have left in the flight. But, that would mean they’d have to look at their watch, then do the math. Especially when we’re landing in a different time zone–it’s easier to just call up front and ask me. Right?

Well, maybe not me. My answer is usually relative: “About ten minutes early.” Which means: look at your watch. This is your flight–know your own schedule.

Or, look at the gee-whiz panel at your station, counting down the minutes. Or, do the unthinkable: ask one of your colleagues in the back? Nah. Whether it’s the temperature or the time, rather than ask each other, just call up front. All of you–not one call, but four, because you can’t hear the dog whistle or talk to each other. Even had a fifth flight attendant, just riding the aft jumpseat home 130 feet behind me, ask me to “cool off the back.” Seriously?

Okay, it’s a given: we work together, fly together, even all talk–sometimes at once–to each other. We just don’t communicate very well. So, my new policy is this: any time the crew interphone chimes, I look to the F/O and say, “It’s for you.” He’s the one screwing up the temp anyway.

And at least I’m happy, and that’s a start.

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Ask an Airline Pilot: Why Do I Feel So Worn Out After a Flight?

Posted in air travel, airline pilot blog, airline pilot podcast with tags , , , , , , , , , , on September 19, 2012 by Chris Manno

This is a question that I get asked by the most astute travelers: why do I feel physically worn out after a routine flight?

That’s a very good question, born of savvy observation among those passengers who fly often. And they’re right: flying has a direct physical impact on your body for very clear reasons, which I’ll explain. And–good news–there are some things a passenger can do to minimize many of these effects.

The culprit with the most insidious effect is one of the most obvious factors in your flight–and also the most underestimated, and that is, ALTITUDE. I’m only talking about the aircraft’s altitude indirectly, because what really affects you as a passenger is the cabin altitude.

The controlling factor in the cabin altitude is the the hull design of the aircraft. Because the pressure at altitude is a fraction of that at sea level, the aircraft’s pressure hull must have the strength to hold survivable (for humans) pressure in an extremely low pressure environment at altitude. For the sake of structural integrity, the difference between inside and outside pressure has to be minimized and the way to do that is to allow the cabin altitude to climb with the aircraft altitude, gradually, to a higher altitude to minimize the differential pressure.

The picture above is of a pressurization gage that shows aircraft altitude, cabin altitude–and the difference between the two. The aircraft’s pressurization system gradually raises the cabin pressure with the climb to altitude to keep the differential within the aircraft hull’s design limits. The result? At 41,000 feet, the aircraft cabin is over 8,000 feet.

That’s like being transported to Vail, Colorado (elevation, 8,000′) in a matter of twenty or thirty minutes. Suddenly, your body must make do with a significantly reduced partial pressure of oxygen, and this after being depressurized like a shaken-up soda can: every bit of moisture in your body–and gasses as well–are affected by the rapid (compared to a gradual drive from sea level to Vail) change of pressure.

This affects your body like the bulging of a balloon animal: the pressure reduced around you makes everything swell. Maybe not as dramatically as the balloon animal, but with definite and perceptible effect. And that cycle is repeated on the way down, in the opposite manner: your body must accommodate the repressurization.

Some people are more susceptible to the effects of altitude than others: I’m one who doesn’t feel well doing prolonged physical activity at altitude above 5,000 feet. I don’t like skiing or the outdoors type stuff in the mountains because of the flu-like effects of physical exertion at higher altitudes. Common side effects, or what’s called “altitude sickness,” include flu-like symptoms such as headache, body and joint pain, fatigue and a feeling of being out of breath.

If you’re the type who is susceptible to “altitude sickness” in any degree, you shouldn’t underestimate the effects of cruising for several hours at a high cabin altitude.

Next on the list of stress factors has to be humidity–or more importantly, the lack of humidity at altitude. The cabin air comes from outside at altitude where the humidity is around 1% to 2%. Fresh air is drawn in, heated, then mixed with cooler air to provide a comfortable cabin temperature. Mythbusters: I’ve heard the urban legends about “restricted air flow” to save money; recirculated rather than fresh air in airline cabins. That’s all bunk, at least in Boeing and Airbus aircraft. The cabin pressure is maintained through constant circulation and in the Boeing, large fans draw the air throughout the cabin and cargo compartments, then through the electrical compartments for cooling, then to an outflow valve for metered release with respect to a stable cabin altitude.

The pressurization and air conditioning systems work great, supplying fresh, conditioned air but . . . the humidity is very, very low because the source air at altitude is exactly that way. So, if you as a passenger aren’t drinking water constantly–you’re going to feel the effects of dehydration quickly at altitude.

The last of the major but often underestimated stress factors is also obvious but insidious: noise and vibration. Consider the basic fact that each engine on a 737 weighs over a ton and each has a core that spins at over 30,000 RPM at idle power. At cruise power, the vibration is subtle but distinct, transmitted through the airframe to everything and everyone on board.

That has a physical side effect added onto the motion effects of flight: pitch and roll changes in combinations you don’t experience on Earth. Like trains, ships and cars on a rough pavement, vibration is transmitted to your body and has a wearing, fatiguing effect.

Noise? Absolutely: there is a layered level of noise from engines, airstream outside and air flow inside that is both fatiguing and cumulatively, wearing.

What can you do about these three factors that can literally wear you out as you travel by air? Let’s start with the last factor: noise. This one has a really easy solution:

Earplugs. The foam kind, available in any hardware store. We use them in the cockpit all the time, because wind noise in the pointy end is much louder than in the back, depending on altitude and speed. They’re disposable, they’re cheap–and they work. You can still hear normal conversation just fine and the important thing is that they will reduce the fatigue level you will feel after a long flight. Try them on your next flight.

Low humidity? This is tied to the altitude effects as well, and this is a simple solution as well: hydration. Certainly on board you should be drinking plenty of water (yes, you’ll have to bring water with you–it’s available in airports everywhere; if you’re really cheap, just bring a bottle and refill it at a water fountain in the airport) but also, you need to think ahead.

Like the preparation for a marathon, you need to stay well-hydrated the day and night before the event.

If you step on board marginally hydrated or actually slightly dehydrated, the 2% humidity at cruise altitude will outpace any attempt you make to catch up, much less keep up. Coffee? Alcohol? Diuretic soft drinks? See photo above.

Finally, the high altitude effects of cruise flight. The good news is, going forward, that the next generation aircraft like the 787 “Dreamliner” are capable of maintaining significantly lower cabin altitudes during cruise. This is very important on long flights and the fact that Boeing designers recognized this passenger stress factor and have designed a way to minimize the effects underscores my original point about the stress.

For now, though, the best you can do is to deal with the other two key stress factors–hydration and noise–and simply try to be in decent physical shape: those who are suffer less with the stress of altitude exposure.

In the final analysis, you can’t completely avoid the physical stress of air travel without avoiding air travel itself. But, if you are a savvy traveler, you can at least recognize the effects and take simple steps to minimize the effects of air travel on your body and ultimately, your trip.

Bon voyage.

Ask an Airline Pilot

Posted in air travel, airline pilot blog with tags , , , , , on August 13, 2012 by Chris Manno

Have questions you want to ask an airline pilot but don’t have one handy? Or you notice that they’re busy with pre-flight duties (thanks for noticing and for not interfering) so you don’t say anything?

Here are the questions I get asked most often, with the best answers I can come up with:

1. Do personal electronic devices interfere with aircraft systems?

Answer: Here’s what you have remember about aircraft systems and electronic devices. First, many handheld or personal devices create an electronic signal, particularly if they have a cord of some type. Aircraft systems are constantly seeking out specific electronic signals from everything from Global Positioning Satellites to ground-based antennae for communications and navigation.

Further, even within the aircraft, there are electronics creating and transmitting electronic signals between systems for both navigation and control of other aircraft systems–including flight controls. It’s important that only the required signals are received by specific on-board systems and yes, extraneous electronic impulses can interfere with those required for control of various navigation and control functions.

Most have backups with non-electronic signals. For example, on the 737-800, the engines are controlled by an advanced solid-state dual system we call EECs. For every throttle movement, the EEC computers are sending impulses to the fuel control based on hundreds of minute electronic inputs from computers, sensors, instrumentation, and pre-programmed performance parameters. Worst case, though, if there is an interference problem or a failure, the system reverts to a “dumb” mode, simply using the old direct throttle and hydro-mechanical linkage. So in this case, any electronic interference is not a major problem–just an inefficiency.

Ditto in the approach mode: the aircraft navigation systems are receiving and displaying course and altitude data from ground-based antennae. If there’s a conflict or interference, we simply don’t use the data. That only changes the minimum descent altitude which again, is an efficiency issue: might have to divert if we can’t descend below the weather.

A final and more important consideration is in play though, when it comes to personal handheld devices during critical phases of flight. That is, the personal attention of the passengers–which needs to be directed to the crew. Not watching a video, or typing a text message, or listening to music. In critical phases of flight, passengers need to focus on and attend to the instructions of the crew.

2. How fast are we going on take-off and landing?

Answer: Well, it varies based on aircraft weight and flap configuration, but you can pretty much figure in a large jetliner that both the take-off and touchdown speed will be between 130 and 155 miles per hour (of course we use nautical miles per hour for our calculations). The jet will normally fly about ten knots shy of the computed take-off speed, but that is a minimum that doesn’t ensure maneuvering speed margins.

Speeds on takeoff and landing are always a spectrum of choices for the pilots. On take-off, we consider the climb gradient required due to obstacles or terrain ahead. More flaps offers a higher climb gradient and a lower take-off speed. A lower flap setting requires more runway for take-off but most likely can allow for a reduced power setting, important points for engine life and even noise considerations.

The short runway at Santa Ana's John Wayne Airport is always a performance challenge for both take-off and landing.

On landing, the higher flap setting allows for a slower approach speed, which is key when landing on a short runway. An interesting point you may not realize is that by design, the profile speeds for the stretched aircraft like the 737, 757 and 777 are artificially boosted to keep the nose position relatively low through both the take-off and landing rotations. That’s because the geometry of the stretched fuselage leaves a critically small margin between the tail and the runway on both maneuvers: in the 757, you have about 18 inches between the tailcone and the runway on take-off rotation and landing flare–not really much clearance. The higher approach speeds keep the nose lower.

Of course, upon landing on a short field like Santa Ana or even Washington Reagan or LaGuardia, the last thing you want is excess speed to absorb in stopping. No worries though: Boeing has given us the toughest landing gear and brakes in the air today.

3. Are most landings done by automation?

Answer: No. In fact, very few are, for a couple of good reasons. First, the ground based antenna must be kept free of any obstructions, and that specification and guarantee is only provided in very low visibility, which in itself is unusual. I mean that literally too: the airport physically ensures that no ground traffic of any kind–airport vehicles or aircraft–taxies by the antenna while an aircraft  is using the signal for landing guidance.

If the antenna isn’t specifically certified as free from any interference, the landing will not be automatic. Also, a special crew certification is required for autoland, and not all aircraft are equipped to do it: MD-80s, 757s, 767s and 777s  can all autoland if the correct conditions exist. But the 737-800 I fly does not have the capability to autoland. Rather, we have the cosmic Heads Up Display that allows me, the captain, to land with no ceiling and only 300 feet of forward visibility:

I can “see” the runway through whatever weather shrouds the actual runway–because the GPS system synthesizes a runway which exactly overlays the actual runway and I’m watching it all the way down. So at least in the 737-800’s I fly, you’ll never have an autoland and will always have a hand-flown approach and landing. And even when I flew the autoland-capable MD-80, I’d perform maybe one or two actual autolands per year. So the answer, generally speaking, is no, aircraft aren’t normally landed “automatically.”

Whatever the visibility, the Boeing-737-800 at my airline is landed by hand.

The last question that goes with the group of “most asked” I won’t even answer, and I usually don’t when inevitably, someone has to ask: “Where is the   nearest bathroom?” The answer is, “I’ve answered the important questions above–I’ll leave this one up to you.”

Boeing Instructor Captain Mark Rubin

Posted in airline pilot blog with tags , , , , , , , , , on January 25, 2012 by Chris Manno

He’s amassed over 20,000 hours in the Boeing 727, 737, 757, 767, 777.

JetHead Live goes one-on-one with

Boeing Instructor Captain Mark Rubin

Click Here to listen and/or download

All JetHead Live podcasts available free on iTunes. Just click on the logo below.

A Wing and a Prayer, and the Everlasting Moon.

Posted in air travel, airliner, airlines, flight crew, jet, jet flight, pilot with tags , , , , , on January 7, 2012 by Chris Manno

Only poets and saints have ever flown like this, riding a wing and a prayer. Darkness like sadness, spread to the end of the world, save the glow of cathode ray tubes painting the hearbeat of the seventy ton schooner, riding the howling eastbound jet stream.

That’s always a rush, surfing that gale, especially this time of year. But that’s what it takes, that’s what the 160 folks in back expect; never mind the details of turbulence and winds and fuel flow–those are yours to deal with alone. Just the way you like it.

You catch a glimpse back there now and again, but the view’s better ahead; quieter, a vortex of unseen electrical, pneumatic and hydraulic function, the lifeblood of the jet, blooming through the animated tapestry sprawled from bulkhead to bulkhead and overhead and nowadays you don’t know where the jet ends and you begin. Not that it matters: you’re comfortable in your second skin, aluminum and titanium, blood and bone–it’s one and the same for now.

And in the reassuring light of the cabin, what they don’t know won’t hurt them: through the night, an alabaster glow fires up the undercast ahead, swelling and spreading like a false dawn. The spectral blister swells to bursting and time reels backward for you–the western Pacific; the South China Sea, a world of time and distance ago.

Dark as deep space, a cloud deck below, the endless nothing above. Jets everywhere, formations in and out, stacked and you busy with courses and altitudes, your jet’s performance–then that ghostly glow below; angry rising–before you think you say it, as soon as you do you’d beg the words back on your life: “What the hell is that?

Ivory-bone light melts up through a swirling veil of striated cirrus laid like a blanket on the Korean countryside frozen cold in the dead of winter.

“The moon,” comes the deadpan reply from another aviator. And you just let that smolder and die in the darkness; betrayed by the indifferent moon climbing it’s sky arc just like you did yours. What the hell–we’re pals–we’re going to be, through thousands of air miles over years and skies around the globe.

And it’s the aviation childhood still: less than a thousand hours of flight time; everything’s a wonder, an answered prayer or a silent wish playing out across a thousand miles at Mach speed. Like today: major league tailwind drives the groundspeed up to nearly 700mph.

Unseen from above, the miles past so fast sometimes. And that glow below, now a thousand years later and as many miles hence, you just know. Time to start down–just as your old friend climbs up. We’ll trade spots in the sky, share one more curtain call.

And surely we’ll cross paths again, however many more times we can. No surprise now–but just as stunningly bright as ever. It’s all too familiar, but in a good way: a wing and a prayer and the everlasting moon; the the essence of flight that never loses its brightness.

From flying fighter jets in the Netherlands to the captain’s seat on a KLM jetliner, Captain Martin Leeuwis has done a lifetime of amazing flying.

We go one-on-one with him on our audio podcast next week.

And later this month: 3-time space shuttle astronaut Mike Mullane joins us on JetHead Live.

Subscribe now for updates!

Pilot Report: Boeing 737 vs. McDonnell-Douglas MD-80

Posted in airliner, flight crew, jet, pilot with tags , , , , , on December 17, 2011 by Chris Manno

Now that I have nearly a thousand hours in the left seat of the Boeing 737-800, and having as well over 15,000 in the MD-80, I feel qualified to make some judgments about how the two stack up against each other.

For me, there’s one hands-down winner. I’ll get to that.

But first, looking at it from a hands-on pilot perspective, let me say what I think are the crucial factors in both jets, then compare them. And I’ll do it in order of importance from my line-swine pilot view:

1. Power: never mind the technology difference between the General Electric JT8D turbo fans on the Maddog and the CFM-56 high-bypass fans on the 737. It’s the thrust difference I want in my right hand when I’m trying to lift 170,000 pounds off a runway. And technology aside (I’ll get to that), the three full power options (22,000, 24,000, and 26,000 pounds of thrust) plus the bonus kick up to 27,000 pounds per engine on the 737 for special use beats the snot out of the 19,000 flat rated and standard de-rated engines on the MD-80. Yes, the -80 weighs less than the 737 (max of 150,000 vs. 174,000 pounds), and no, I don’t have each plane makers’ specs, but the thrust-to-weight performance from the left seat feels substantially more secure and significant from the 737.

You notice that right away when you do a static takeoff with the 737 at all weights: you’ve got buttloads of giddyup (I think engineers call it “acceleration,” but then they don’t actually feel it on paper versus in the cockpit blasting forward–that’s “a buttload of giddyup”) shortening  those critical moments of vulnerability between brake release and V1.

I have no idea what engineers think of when they look at thrust and take-off advantages, but any pilot with experience knows that those seconds before reaching flying speed are the most vulnerable, particularly close to max abort speed, because I’d rather take any problems into the air than have to wrestle them to a stop on a runway. The MD-80 has good smash at mid to light weights, but in crucial situations (Mexico City, for example, or on a short runway on a hot day) the 737’s CFM56’s rule. I need the shortest possible period of on-runway vulnerability; I know engine hot-section limits and longterm life are important too, but the CFM56 achieves better on-wing engine endurance in operation than the JT8Ds, year over year.

Ditto for a go-around or windshear options: the MD-80 is famous for it’s slow acceleration–I’ve been there MANY times–and when you’re escaping from windshear or terrain, I can promise you the pucker factor of the “one, Mississippi, two Mississippi” on up to six to eight seconds will have your butt chewing up the seat cushion like horse’s lips. Not sure if that’s due to the neanderthal 1970’s vintage hydro-mechanical fuel control (reliably simple–but painstakingly slow to spool) or the natural limitation of so many rotor stages. But the 737’s solid state EICAS computers reading seventy-teen parameters and trimming the CFMs accordingly seem to give the performance a clear edge. And a fistful of 737-800 throttles beats the same deal on the Maddog, period. Advantage, Boeing.

2. Wing: let me go back in time. I also flew the F-100 for a couple years as captain. That was a great jet, with a simple wing: no leading edge devices. Coming from jets with slats the feel was clearly different on take-off, where there was a distinct (if you’re a seat-of-the-pants guy, and that’s all I’ve ever been) translational period between rotate and lift-off due to the hard wing. Ditto in the flare and in some reversals in flight like on a go-around. Not a bad thing, just something you had to anticipate, but not a warm-fuzzy in the seat of your aerodynamic pants.

Stretched jet, stretched wing.

That’s a good analogy between the Boeing versus the Douglas wing: you feel the generous lift margin in the 737. That’s because when Boeing stretched the jet to the -800 length, they expanded the wing as well. That wing was already loaded much lighter than the DC-9 wing which Douglas didn’t enlarge when they added to two fuselage plugs plus about 15,000 pounds to the MD-80. Longer and with better cambered  (look at the DC-10, and no dihedral) airfoil is the Boeing design and I’m grateful for their foresight and superior engineering–especially at the top end of the performance envelope: you need anti-ice? No problem–turn it on. The Maddog? Better be 2,000 feet below optimum, or prepare for stall recovery–and anyone on the -80 fleet knows I’m not exagerating. Wing performance? No contest: Boeing.

3. Handling: again let me go back in time. Flew the T-37 like every new Air Force pilot up until recently–then moved on to the T-38. Using standard Tweet inputs on The Rocket would bang your helmet off the canopy because of the boosted flight controls, giving you 720 degrees of roll in a second at full deflection.

That’s the 737 compared to the MD-80: no aileron boost on the -80, and little help from the powered rudder–because of the long fuselage length and relatively short moment arm between the vertical fin and the MAC (Mean Aerodynamic Chord), the rudder seems to only impart a twisting moment that’s pretty useless. So it’s a wrestling match for roll control, in and out of turns with the -80.

I still tend to over control the 737 in acute roll situations (e.g., the 30 degree offset final at 300′ AGL required in and out of DCA) due to previous brain damage caused by years of arm wrestling the MD-80 around tight corners. But with the 737, the seat-of-the-pants security of that generous wing is apparent at all speed and altitudes and the hydraulic aileron boost gives you the muscle to command a smooth and prompt response. Handling? It’s all 737 for me, including on the ground: new MD-80 captains will need Ibuprofen to counter the wrist strain of the nosewheel steering, two-handed in tight spots. I don’t miss that at all.

4. Cockpit layout: okay, give the -80 its due–that was one comfortable nest once you got settled. But that’s as far as it goes for me. Yes, I know the 737 kitbag position is inaccessible. But American Airlines is the first airline certified by the FAA for iPad use from the ground to altitude. Kitbag, what’s a kitbag?

MD-80 left seat–HSI? Where is it?

Trade-off? The MD-80 HSI is obscured by the control yoke. Are you kidding me? Like you might need lateral situational awareness for trivia like, navigating? Flying an approach? I spent 20+ years working around that human factors engineering failure–I’m grateful for the Boeing engineers who gave me seven 9″ CRT flat plate displays with every parameter I could want displayed digitally and God bless them all–a Heads Up Display! Lord have mercy, even a simpleton has a crosscheck in that jet thanks to the God of HUD.

The 737 doesn’t have the elbow room you might like and everyone who I fly with who has come off the big Boeings (757, 767, 777) gripes about that. Fine. I’m all about performance and the flight displays, computers, communications and advanced Flight Management Systems in the 737 avionics suite beat the pants off of the 75 and 76–and the HUD tops the 777 as well. Nuff said: gimme the Guppy cockpit over the Maddog. Boeing put everything I need at my fingertips, and it’s all state-of-the-art, whereas Douglas engineers threw everything they could everywhere in the cockpit and slammed the door.

My 737 home.

So there you have it: power, wing, handling and even by a narrow margin, the cockpit too. I’m a Boeing guy, back from wayward days flying Douglas metal from the DC-10 to the MD-80. In my experience as a pilot, in my hours in both Boeing and Douglas jets, I’m grateful to be flying the best jets in the sky. Now you know which are which.

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