Embraer Revisited. . . My Bad

Well it seems that in my haste to wrap up the regional jets, I skipped Embraer's other line of regionals, the ERJs. Although certainly less impressive than their E-Jet relatives, the ERJ 145 family of aircraft is nevertheless an important member of the global regional fleet.

The ERJ 135/140/145 are very small turbofan powered regionals that actually fill the niche below the Bombardier CRJ100/200 that was mentioned in the previous post. The 145 family was developed starting with the largest version, the ERJ 145. It first flew in 1995 (in its final design; it originally flew in 1989 but was deemed unsatisfactory and was redesigned) with a passenger capacity of 50. As a side-note that I found interesting, the ERJ 145 was designed from Embraer's turboprop, the EMB 120. Although the ERJ 145 that first flew in 1995 was quite different, it shares the same seating arrangement, range, and T-tail arrangement. To my knowledge, it is rare for a turbofan/jet aircraft to be derived from an existant turboprop airframe (please correct me if I'm wrong). The ERJ 140 variant seats 44, while the 135 seats 37.

Seeing as the both versions have at least 95% commonality with the ERJ 145, with the biggest visible difference being the shortened fuselages, telling these apart from one another is very difficult. To me, attempting to pick apart aircraft that have less than a 15 person capacity difference across three models is pointless. Instead, I'll just describe how to tell the ERJs apart from their closest lookalikes, the CRJs.

As you can see above, the ERJs have very, almost comically long noses, which taper entirely from top to bottom. Both these characteristics are exaggerated compared to the CRJs. The other easy way to tell them apart are the ERJs' engines. All ERJs have Rolls-Royce Allison AE3007 engines, which are entirely encased by the bypass air nozzles (the white casing around the engine in the picture above). That is quite different on the CRJs that have the rear portion of the engines, namely the combustion chamber and the turbine, exposed.

Currently there are a total of 697 ERJ 145 variants in service. The airline that I most associate with the ERJs is American Eagle Airlines which operates 200, as they use a ERJ 145 to connect to the American Airlines hub in Chicago from Rochester, such as the one below at O'Hare:

But the overall largest operator is ExpressJet with 244 ERJ 145s. ExpressJet operates under the banners of both Continental Express and United Express.

Bombardier. . . Those Damn Canadians

(CRJ200)

The final key Western commercial airplane manufacturer is Bombardier. Boeing, Airbus, Bombardier and Embraer are the four largest Western airliner manufacturers, in that order. Bombardier is a Canadian company that specializes in regional jets, turboprops, and corporate jets. Bombardier owns both Learjet and deHavilland Canada, which explains the later two of its specializations. But out of respect for deHavilland's amazing designs, I will cover the turboprops (the Dash 8/Q series) in a separate post focusing on deHavilland Canada.

Once you push aside the Learjet and deHavilland families, Bombardier only has two lines of regional jets, which are quite prevalent. In fact, Bombardier's regional jet families are very similar to the Embraer E-Jet families in their composition. There are two "sets," the CRJ100/CRJ200, and the CRJ700/900/1000. Each subsequent type is simply a stretched or larger version of the previous model. So realistically, you only need to be able to identify the families as a whole, instead of each type, just as with the Embraers.

First I will explain how to identify Bombardier regionals in general. They are very easy to spot, with the only similar plane in their class being the increasingly rare Fokker regionals. What stands out the most is that the engines are mounted in the rear on the fuselage. The wings are swept back at a steep angle. They are like much smaller McDonnell-Douglas MD80s, except the noses are different. The Bombardiers are similar to the Embraers as the noses are like the bullet trains, with almost the entire taper being down from the top to the bottom. To me, they kind of look like pencils as two-thirds of the narrow fuselage is forward of the sweep wing and the nose is pointy. Finally, the engines are quite distinctive. They have a very cylindrical forward section (bypass duct) and a cone-like, metallic colored rear section that is almost equally long (which is unusual), as you can see here:

(CRJ100)

So what's the difference between the CRJ100/200 series (which are the two above pictures) and CRJ700/900/1000 series? Simply put, size and a few added bells and whistles. They all have similar ranges, speeds, and ceilings. They also increase in capacity at quite regular intervals, unlike the Embraers, so they cover a lot of the regional market. Instead of differentiating each type, I'll just give you the range of capacities and first flights.

The CRJ100 and CRJ200 are the same capacity at 50 passengers. The CRJ200 is just a reengined version with slightly better range and fuel economy than the 100. The CRJ100 first flew in 1991.

The CRJ700/900/1000 series transports 70 to 100 passengers, with each subsequent model carrying about 20 more people. The CRJ700 first flew in 2000, and the CRJ1000 (which looks almost awkwardly long for the size of its engines, see below) first flew in late 2009 and has yet enter regular service.

(CRJ1000)

How do you tell the difference between the two families? Well, you can always count the windows and estimate the seating capacity, but that's boring and difficult. Sometimes you can just eyeball the fuselage length and know if at least its not a CRJ100/200. The only way I know to tell between the CRJ200 and CRJ700/900/1000 is that the latter series has leading edge slats. From a distance slats can be very hard to spot if they aren't deployed (they shouldn't be on the ground or in cruise). But if you do happen to see slats on a CRJ, then you know that it has to be CRJ700/900/1000. (If you don't know what slats are, just tell me and then I can make a post on them)

Who uses Bombardiers in the U.S.? Well, almost everyone. These are extremely popular aircraft with the legacy carriers as they can be used for gazillion smaller airports around the country (including, surprise! Rochester) Delta Connection alone (or its subsidiaries) operates an incredible 381 CRJ200s, 66 CRJ700s, and 101 CRJ900s. Considering that Delta/Northwest, the largest airline in the world (for now, United/Continental is forecasted to surpass it), only operates 18 B777s and 16 B747s, you can see the huge numerical difference between the big widebodies and the regionals. Low-cost airlines tend not to use the Bombardiers as they are too small for their operations, which stipulate larger aircraft (usually E-Jets, A320s, B737s) to lower the cost per passenger seat per mile.

Is this legal?

Have you ever been plotting along in your Cessna, Piper, Cirrus, Beechcraft, or Diamond and wondered, hey can I throw my bag of flour out the window and not be hunted down and killed by the FAA? I know I have. Just in case you were, I thought I'd clarify the Federal Aviation Regulations (FARs) on dropping objects from airplanes.

To most new pilot's surprise, it actually is legal to drop objects from your airplane... that is only if no property or person is damaged, maimed, or killed. So as I'm flying over the Allendale Columbia campus, I could drop a sack of flour onto the courtyard, as long as nothing is damaged and I don't hit anyone. Although I'm sure they could sue the bejesus out of me.

But you'd better have amazing aim or trig skills because you won't be able to fly very low. The FARs put the nail in the coffin for low-level flour bombing (at least in monitored areas). There are three regulations that make up the "minimum safe altitudes" rules.

Over congested areas: An altitude of at least 1000ft above the highest obstacle within a horizontal radius of 2000ft of the aircraft must be maintained over any congested area of a city, town, or settlement, or over any open-air assembly of people.

Over other than congested area: An altitude of 500ft above the surface must be maintained except over open water or sparsely populated areas. In that case, the aircraft may not be operated closer than 500ft to any person, vessel, vehicle, or structure.

General Anywhere Rule: The pilot must maintain an altitude which, in the event of an engine failure, will allow an emergency landing without undue hazard to persons or property on the surface.

The 500ft rule is the most important one when it comes to bombing anything, although the FAA could screw you with the Anywhere Rule anyway. Normally, flour bomb competitions (which happen quite often, as it is a major event at National Flight Team competitions) have the target on a closed runway, as there are no altitude restrictions set in stone (the anywhere rule is still applicable as long as the aircraft is not landing or taking off) over airports.

So in summary, yes dropping objects is legal, but it comes with a laundry list of ifs and buts. Of course you could just fly off the beaten path where there is no radar coverage and then obscure your aircraft registration so no one could report you.... but I won't never recommend or condone such actions. ;)

The Embraer Regionals

Instead of doing all of the regionals at once, I have decided to do them in separate posts to encourage me not to be lazy. Before I start talking about the E-Jets though, I should define what is a "regional" airliner. Regional jets or turboprops are usually short-to-medium haul (topping out at around 3,000nm) and seat up to 120 passengers. This includes the smaller B737 and A320 variants that are considered large regionals. These rules are not absolute. For example, some might considers the smaller MD80s as regionals, but I don't. Most of the time regionals feed larger aircraft and airlines by connecting low density markets (such as Rochester or Springfield, Illinois) to airline hubs or larger airports such as JFK or LAX.

The Brazilian aviation company Embraer has largely produced business jets. But since the E-Jets series introduction into commercial service in 2004, Embraer has been steadily becoming a bigger player in the regional airliner market. The E-170/-175 and E-190/-195 are medium haul, narrowbody twins. They are considered "large" regional jets with their passenger capacities ranging from 80 to 122 passengers in high density configurations (i.e. single class, no leg room seating arrangement). The E-Jets or ERJs as they can be called are essentially four variations on the same general design. Each variant is really just a stretched version of the previous one. The E-170/-175 have the same wingspan, fuselage height and width, and engines. The E-190/195 are also similarly paired with the same wingspan, fuselage height and width, and engines. According to Wikipedia, the E-170/-175 and E-190/-195 families have 89% commonality, whereas each family pair has 95% commonality.

Anyway, how do you spot the ERJs? Telling them apart from one another is probably really difficult, so I won't get into that.

The best way to differentiate an ERJ from say a A320 or B737 is the nose. The nose slope is similar to the much larger B757 in that its a straight angle from the top of the fuselage to the bottom, like a high-speed rail locomotive*. They kind of look like mini B787s as well. Also, I believe the E-Jets are the smallest (especially the -170/-175) twin engine jet liners with the engines below each wing in pods. The E-190 and E-195 are similar in size to its chief competitor, the A320. Finally I have noticed that the windows on the ERJs are spaced farther apart than most other below wing twins, i.e. the B737 and A320.

The E-Jets are beautifully designed, efficient aircraft, which explains their success. Their largest operator is JetBlue, who operates 41 E-190s with 64 still on order. If you ride JetBlue, either you're on a E-190 or A320.

*Here is a picture of a high speed locomotive just in case you don't know what I'm talking about:

What do flaps do?

The 747's (pre-747-800) beautiful triple-slotted flaps. These have DRAMATIC effects.

The old 737's deployed slotted flaps.

This diagram is a good basic summary of wing components. Of course, every plane is different, but this can act a general guide. When you're actually in a plane, it often easier to figure out what everything is based on what movements its making when.

As you can see, normally on larger airliners there are two sets of flaps, inboard and outboard. On smaller planes, the wings are too short to have two sets of flaps be practical. Flaps are usually only used during landing and takeoff and have two functions. When lowered, flaps increase the wing area, thus increasing the amount of lift the wing is generating. Another way of looking at it is that flaps decrease the stall speed of an aircraft, allowing it to fly more slowly without dropping out of the sky. The second force resultant of lowering flaps is an increase in drag. Since flaps drop down (at varying angles depending on the aircraft) from the wing, they create lots of drag, helping the aircraft slow down. Flaps are especially useful as they allow the pilot to decrease the angle-of-attack of the aircraft without increasing the airspeed. (Angle-of-attack is a fancy pilot word for pitch. When a pilot lowers the nose, he is decreasing the angle-of-attack. Normally this would increase the airspeed. But with flaps down, the aircraft will accelerate much more slowly as the flaps are generating tons of drag.)

Flaps have variable settings, measured in degrees that will determine how dramatic their effects are. I will use my little Cessna 152 as an example:

0 degrees: Flaps are not deployed and are thus not generating any additional aerodynamic forces.

10 degrees: Flaps are 10 degrees down from the chord (the line from the leading edge to the trailing edge of the wing). At this setting, they are sensibly (as in I notice) only generating additional lift. Typically I will use this when I want takeoff in a slightly shorter distance.

20 degrees: The flaps start generating some drag, meaning that if during flight I were to lower them straight through to 20 degrees, you would feel some negative acceleration. Otherwise yet more lift.

30 degrees: This is the normal landing setting. The plane significantly decelerates and you would be thrown forward into your seat belt if they were deployed to 30 degrees midflight. (As a side note, flaps can only be deployed below a certain speed (Vfe), usually well below cruising speed, otherwise the pilot risks damaging both the flaps and the wing.) Here the lift and drag is very high. Normally, in my Cessna, 30 degrees of flaps was the setting that would allow me to fly the slowest without stalling.

40 degrees: I rarely use this puppy. At 40 degrees, far more drag is being generated than lift. This is used to lower your altitude as fast as possible while staying within a certain airspeed envelope. I never would land with 40 degrees unless absolutely necessary, as the flaps are at such a steep angle that the wind can catch them like a sail at low speeds and balk my landing.

The summary of what each setting is used for basically demonstrates how flaps are used in general. Low flap settings are used for takeoff to increase lift for a given speed, thus shorting the take-off distance, and to slightly help slow the aircraft during landing. High flaps settings are using during landing to allow the plane the fly much more slowly while not risking a stall, as well as aiding the pilot in slowing the aircraft down during approach.

There are many different types of flaps, each with their own advantages and disadvantages. But instead of overwhelming you with all that unnecessary knowledge, I'll just show a little diagram of what they look like and end there. My boring little Cessna had plain flaps of course.

Why do three engines have humps and one does not?

You'll notice that the outer engine in the third picture is the only engine without a "hump" that runs all the way to the cowling. And, if you remember, no other engines in the pictures I've shown you so far have had these humps. These four engines are from the Boeing 707 (first flown in 1957), the plane that ushered the world into the jet age in the late 1950s. I thought that the interesting question (to me) of why those engines are different would be a good introduction into Bleed Air Systems and their outdated counterparts, Turbocompressors.

Bleed air systems are (or soon to be "were") a key system within most commercial airliners. Bleed air is quite simply air that is taken or "bled" from the jet engines, usually from after the compressor stage and before the combustor (so there is no fuel in it). Since the air is bled from after the compressors, it is both very hot and under very high pressure. This hot and high pressure air is fed through pneumatic lines into the aircraft and can be used for a variety of functions including heating, de-icing, pressurization, and actuators. Bleed air is being (very) slowly phased out of newer aircraft designs because of its inherent inefficiencies. Bleeding air from the engines increases fuel consumption for a given output of thrust. Also, the air that leaves the engine through the air lines is far too hot to be immediately used in the cabin, so it has to be refrigerated (entailing more weight for chemicals and electrical components). Next generation planes such as the Boeing 787 (which first flew in late 2009) rely on electrical generators for heating, de-icing, etc. instead of bleed air.

So why the weird engines on the 707? The Boeing 707's comparatively archaic turbojets were not powerful enough to loose air to the bleed air system without seriously decreasing the performance of the Pratt & Whitney JT3Ds. Instead, the Boeing 707 has turbocompressors mounted above three of its four engines (thus explaining the humps). The turbocompressors are mini turbines that are mechanically driven by the main turbojets, and compress air from their own independent air inlet directly above each turbojet's cowling (so as not to draw air away from the JT3Ds). Since three turbocompressors could provide ample air for the other systems on the aircraft, there was no need to add the unnecessary weight of a fourth one on the port outer engine.

Just as a final useless factoid, the first commercial engine designed to provide bleed air was the Pratt & Whitney JT8D. The JT8D was first used on the Boeing 727 (first flown in 1963), the next airliner designed and built by Boeing after the 707.

Why the "Step"?

I decided that in the interest of me posting more, that I'd change my writing strategy. Instead of doing infrequent long posts, I'm going to try to do daily short posts. Perhaps every once and a while I will do a novel, but for now, I will change to something akin to the "Fact-a-Day" method.

For my first act, I'm going to answer the seldom asked question, "why do flying boat hulls have the step on the bottom?" The step is the abrupt decrease in the hull chord usually about midway down the bottom of the aircraft, as can be seen on the Bombardier 415 in the picture above. First it is important to understand the difference between a flying boat and a float or seaplane. Put quite simply, a flying boat is a plane that lands directly on its hull into the water, just like a boat (who would have guessed?). A flying boat is (I am pretty sure) always primarily designed to be mainly operated on water, although most also have retractable landing gear for landing on tera firma. A float plane or sea plane usually lands on floats that are positioned similarly to traditional landing gear, and can be originally designed for use on land and then retrofitted with floats. Here is an example:

So now that we have that clear, the step on a flying boat or actually on all floats, its designed to aid the plane in breaking away from water during takeoff. When the plane is attempting to takeoff, two forces try their best to keep the hull or float firmly attached to the water's surface: adhesion and vacuum pressure. Adhesion is of course the molecular attraction between water molecules and other compounds. The vacuum pressure is caused when the aircraft pulls up on the water's surface without allowing air into a pocket under the hull, creating a low pressure (which causes the water to "pull down" on the aircraft). In calm seas, vacuum pressure is a particularly annoying problem since when the water is choppy, there won't usually be an airtight seal between the water and the hull. By adding a step, the hull is no longer a long, continuous surface. Thus when the aircraft is at speed, the water flow is broken up underneath the hull, lessening the strength of adhesion and vacuum pressure.

In addition to the step, most flying boats in particular have "breather tubes" which are located just aft of the step. These tubes run from the bottom of the hull to another location on the aircraft that is always exposed to open air. In turn, the spot most prone to vacuum pressure (the area just behind the step) can never form a low pressure as air will be immediately drawn into the pocket through the breather tubes. The tubes can be seem in the picture at this link if you zoom in and look closely behind the step on the hull: http://cdn-www.airliners.net/aviation-photos/photos/1/7/6/0770671.jpg

The Hard One

here we go, same as last time.

#1

#2

#3

#4

#5

A Little Quiz like You Asked For

Just comment the corresponding name to each number over the photo.

#1

#2

#3

#4

#5

Another Plane Spotting One

Now that I've finished up the Boeings and Airbus's, the plane spotting game becomes more difficult as there are a lot of different models and makes out there. This is especially true in the regional market, where there are a large number of players all competing in the more generous short haul market.

But before getting into the regionals, there is still one formerly big player in the medium-to-long haul market: McDonnell-Douglas (MD). McDonnell-Douglas was at one time just as important as Boeing and was Boeing's chief competitor in the 1950s, 60s, and 70s. But in 1997, Boeing and McDonnell-Douglas merged, creating just The Boeing Company. Large MDs are rarer now in the passenger aviation market since they are outdated both technologically as well as by design (for example, the widebody MD is a trijet, which as I explained in the previous post, has fallen out of use). But there is one MD that is still operating in large numbers and its reputation as loud, antiquated, and as fuel guzzlers makes it my least favorite currently operating large commercial aircraft... can you guess which one? The suspense must be palpable. We'll find out in a little bit. Besides that one plane, most MDs have been relegated to the cargo industry. By the way, DC means Douglas, which implies that the type received its designation before McDonnell and Douglas merged in 1967.

DC-10/MD-11

The DC-10 is one of the classic widebody trijets that I wrote about in the previous post. It was first flown in 1970 so it is quite old. The MD11 is simply an updated version of the DC-10, first flying in 1990. Both are medium-to-long haul airliners. The DC-10/MD11 are easy to differentiate from other planes because of the third engine mounted on the vertical stabilizer. It is important to note that the engine cowling/body is not fused to the main fuselage of the aircraft, but is instead raised, a key feature in distinguishing it from its former chief rival, the L-1011 Tristar. In terms of the telling a MD11 from a DC-10, there are a few little tells. A MD11 is longer and has a bigger wing span. But what can more easily viewed from a distance is that MD11s have winglets unlike DC-10s, as can be seen here in this photo of an MD11 (the above photo is of a DC-10):

Both aircraft have been largely removed from passenger service. But they are huge players in the cargo market. Fedex is actually the largest airline in the world in terms of freight tons with its fleet of 74 DC-10s and 59 MD11s (along with a wide variety of other types).

MD-80s/MD-90s

Well if you haven't guess it, then here you go: this is my least favorite aircraft. I hate flying medium demand, medium-haul routes on American Airlines or Delta because invariably you get one of these. MD-80s (with the MD-88 being the most common is U.S. legacy carriers) and MD-90s (for this post's sake, just an upgraded version of an MD-88) are narrowbody, medium-haul aircraft. They are easy to spot, as I believe they are the largest twin aft engined, T-tail airliners in service (the Fokkers might be similar in size but they are far rarer aircraft in the U.S.). They also have the little eyebrow windows above the cockpit like the B737. T-tails (the elevators or horizontal stabilizers being at the top of the tail or vertical stabilizer) are unusual in large airliners, due to the increased weight resulting from the reenforced tail structure and the ability of the aircraft to enter a deep stall and in turn a flat spin, from which it is aerodynamically impossible to recover (in other words, you are 100% screwed). If you would like to learn about deep stalls (buM, bUM, BUM!), just let me know. Well, in my opinion, enough said about this airplane that I don't like at all.

DC-8

This is the oldest plane I have ever talked about in my various plane-spotting posts. It is from the first generation of American jetliners, with the first flight being in 1958. The only reason its on here is that the DC-8 is still used for cargo operations in large enough numbers that I have seen them at airports multiple times. This one is easy to spot, as 99% of the time, they have no passenger windows since they are cargo aircraft, they have four engines despite their small (compared to the A340, A380, and B747) size, and they are the only four engined aircraft with the eyebrow windows above the cockpit. These aircraft are true relics and it is a testament to their sound design that they are still operating in force. Only the B707 trumps it in awesomeness from that era (I suppose that's subjective...). But I figured I would cover the B707 in either an old airliner post or a military post (since the largest current role for the B707 is as an aerial tanker for the USAF) as I have never seen one with my own eyes.

That about wraps up the MDs/DCs, but before finishing this post and moving onto the regionals, there was one now extinct* player in the large airliner market: Lockheed.

Lockheed L-1011 Tristar

The L-1011 was Lockheed's only foray into the widebody jetliner market. It is essentially a double of the DC-10, being a widebody, medium-to-long haul trijet. It also first flew in 1970 like the DC-10. Despite similar specs, the DC-10 outcompeted the L-1011 for reasons I don't feel like getting into here (its a long story). Today, L-1011s are extremely rare in the U.S., but are still used by a few young carriers in developing markets such as Africa and the Middle East. But in the event you run into one (I would be quite jealous), there is a simple way to tell it apart from its only look alike, the DC-10. The L-1011's aft engine cowling is molded into the fuselage, not separated, and the engine's exhaust is directly behind the fuselage. This is because the L-1011's engine is actually inside the fuselage (although separated by an intense bulkhead, in case there is an engine fire or it sheds a blade), unlike the DC-10, which has its third engine entirely in the tail, separated from the fuselage. So if you look at a L-1011's aft engine intake, it forms a stretched "S", which is in turn called a S-duct. Why the different engine positions? Its all about what the designers were looking for. Wiki says it best:

"The main visible difference between the TriStar and the DC-10 that emerged at Douglas is in the middle/tail engine; the DC-10's engine is mounted above the fuselage for more power and easier maintenance, while the TriStar's engine is integrated into the tail through an S-duct (similar to that of the Boeing 727) for improved quietness and stability."

So there you go: the final Western large airliners I believe are worth mentioning in a plane spotting discussion. Next time, I'll go into the nitty-gritty world of regional airplanes, which include the Embraers, Bombardiers, ATRs, Fokkers, Saabs, and de Havillands.

*To clarify, Lockheed (now Lockheed-Martin) itself is not extinct, it just has no offerings in the commercial airliner market, instead focusing solely on defense.

The Finale of the A340, A330, and B777 Question

Now that we've got ETOPS down, lets look at the state of the airline industry in the mid-1980s, just before the arrival of the three aircraft in question.

The Scene

ETOPS ratings were still quite strict, which meant that all long-haul aircraft were either tri- or quad-jets. Of course the king of kings was the B747 that had the furtherest range, highest payload, and four engines to exempt it from ETOPS restrictions. The other big fish in the long to medium haul market were the Lockheed L-1011 Tristar and DC-10 (later the MD11). I'll show pictures of them in my next plane spotting post (or you can just look them up; chances are that you've seen a DC-10/MD11 but not a L-1011). Twin engine aircraft were still stuck in the short to medium haul market as the ETOPS limitations greatly reduced the profit potential of a long haul twin widebody airliner. The most prominent twins on the market were the A300 (first flew in 1972), A320 (first flew in 1987, so quite a late contender), B737 (first flew in 1967), B767 (first flew in 1981), B757 (first flew in 1982), and the various McDonnell Douglases, etc. Here's a quick summary of each of their original design purposes:

A300 -> first twin engine widebody airliner; designed for short-to-medium haul and high density market

A320 -> basically an Airbus alternative to the B737 (and in turn the B717)

B737 -> a flexible short-to-medium and low density market airliner; designed to replace the larger and far more inefficient B707 and similar B717; most successful airliner of all time

B767 -> Boeing's first twin engine widebody; designed to compete directly with A300 and the trijets in the short-to-medium haul and high density market; replaced the aging B707

B757 -> larger capacity narrowbody for the short-to-medium haul market; designed to replace the aging and considerable B727 fleet

(these are very general, obviously each aircraft's design, replacement, and competitor wasn't as cut and dry as that)

The Times They Are A-Changing

As you can see, none of these aircraft are designed for the medium-to-long haul or long-to-ultra long haul markets. But the stars were beginning to align for a radical change. In the 20 years since the market state I described, the trijets have gone from the most common airliners in the U.S. to almost nonexistent, fewer than a dozen B747s are operated by U.S. carriers, the B737NG has replaced the B707, B717, B727, and largely the B757, the B757 has been discontinued, the A380 has taken the crown as the largest capacity airliner, and finally, the A340, A330, and B777 have come to dominate the medium-to-long haul market (with the B777 being the clear front runner).

So what created the change.......? I'm sure you're already putting the pieces together. In 1985, the FAA opened up the ETOPS-120 minute rating for the first time, finally allowing twins to effectively compete with the tri and quad jets over the most lucrative medium-to-long haul market in the world, the transatlantic corridor. Ever since then, the FAA has been steadily increasing the maximum possible ETOPS ratings (so now 95% of the Earth is covered). At the same time, the trijet and quadjet fleets were starting to age and their inefficiencies were beginning to hurt the airlines. Trijets are in no way comparable to contemporary twins since they had the same capacity but far greater fuel consumptions and maintenance costs due to the third engine. Why have three when two will do? The answer prior to the 1980s was three because of the power need and safety restrictions. But by the early 1990s, GE had created the most powerful jet engine of all time, the GE90 (at a world record thrust of 127,900 lbf). Each GE90 is rated at 111,526 horsepower... TWICE the power of the Titanic! And of course these engines are hugely more reliable than the engines from the 1960s and 1970s. So the twin was in. How Boeing and Airbus both predicted and capitalized on this change has shaped the international airport landscape.

Airbus's Answer

First and foremost, its important to understand that the A340 (first flew in 1991) and A330 (first flew in 1992) programs were jointly managed. Both share similar parts and as a result, each was designed to fulfill a different niche. The program was started prior to the ETOPS rating increase in the mid1980s, so Airbus was designing the A340 for long haul and the A330 for medium haul routes. Airbus's failure to predict the opening up of the long haul market for twins is why both aircraft are second to the B777 (which can do both market effectively). But key to especially the A340's survival, both aircraft came out three years prior to the B777, giving them enough time to get a market share, however small. The A340 was able to get its foot in the door since it was more economical than the B747 with new construction materials and systems and it had a higher MTOW and range than the initial variants of the B777. The A330 has been relatively successful since there is more room in the medium haul market for different aircraft. The A330-200 is actually a direct competitor for the B767, so it has not competed very much with the 777, although the A330-300 is comparable to the B777-200 and -300. Airbus doesn't currently have an aircraft that directly competes with all the B777 varients, as they chose to compete with the B747 with the A380, although the development of the A350 is set to change that.

Boeing's Magnificent Answer

I could spend quite a long time explaining how the B777 (first flew in 1994) is such an amazing and successful airplane, whether I talk about it being the first airliner designed on a computer, having the commercial distance record, or having the most powerful jet engines ever made. But instead I'll just talk about the economic reasons its so pervasive. Boeing was lucky in that it started later than Airbus and in turn saw the writing in the wall about twins. The later design dates also allowed Boeing to utilize many new technologies in the "triple 7" that furthered its economical and technological prowess. The first version of the B777 (B777-200) was revolutionary in its efficiency, power, capacity (for two engines), and reach, but the A340 still had it beat. But with the advent of the B777-200LR, -200ER, -300, and -300ER, the B777 beats every single deck (in other words, not the A380-800) commercial aircraft in the world in terms of range and fuel efficiency. That doesn't even bring into play its extraordinary characteristics such as those mentioned above. I don't know if you've ever been on a B777, (if you haven't been farther than North America and Hawaii then you haven't) but listening to those two beautiful GE90s spool up to full power during a MTOW takeoff is awe-inspiring.

In conclusion, the B777 is so successful because Boeing saw and took advantage of a change in the medium-to-long market that resulted from relaxed regulations and new technologies. That is why you are far more likely to see a B777 taking off from Logan than an A340 and to a lesser degree, an A330. If you have any questions, be sure to ask.

Its all about the ETOPS

Before moving on to another plane spotter post or something new, I thought I'd talk about ETOPS and how it explains the designs of the A340, A330, and B777.

So what is ETOPS?

Strictly speaking, ETOPS stands for "Extended-Range Twin-Engine Operational Performance Standards", but its more commonly said to stand for "Engines Turn Or Passangers Swim". ETOPS is the distance (measured by time) a twin engine aircraft (and airline) is allowed to be from an appropriate emergency diversion field should one engine fail. So for example, an ETOPS-90 rating means that the aircraft is allowed to fly a route that would take it no more than 90 minutes from an appropriate airport with one engine running. There are four levels of ETOPS:

• -75
• -90
• -120/138
• -180/207

Originally, prior to the 1980s (in the U.S. under the FAA) the only rating was just "ETOPS" which meant any operation over 60 minutes from a divert field for twin-engine aircraft. This 60 minute rule comes from the days of piston commercial airliners, whose engines were notoriously unreliable. Just as an interesting side note (for me), ETOPS was originally just EROPS, or Extended Range Operational Performance Standards, which applied to all aircraft. ETOPS wasn't created until much later in the 1980s, when the reliability of engines had reached the point where tri- and quad- engine aircraft did not need to follow EROPS.

How are ETOPS ratings decided?

Quite simply, ETOPS is all about engine failure probabilities (or inflight engine shut-down rate) in twin-engine airliners. The lesser the probably one engine will fail, the higher ETOPS rating it can be awarded, and in turn the remoter it's route can be. The failure rate is the magic statistic because the FAA asks three main questions: What is the likelihood one engine will fail inflight? Can the aircraft reach the desired emergency airport from the rating distance on one engine? What is the likelihood the second engine will fail during the diversion? The FAA evaluates each aircraft type AND airline and determines how far they can safely operate from an airport. The FAA take at least the following into account when giving a rating to an airline and its type:

• Engine Failure Rate/Inflight Shutdown Rate
• Crucial Systems (such as Fuel Metering System and Anti-Ice System) Failure Rates
• Crew Procedures and Training
• Maintenance Procedures and Records

Aircraft manufacturers ensure their desired planes will get the appropriate ratings by using engines that have been proved reliable through testing overseen by the FAA and by having redundant systems. Airlines, on the other hand, focus on crew training and enforcing strict maintenance procedures.

As a side note, when I read "What is the likelihood the second engine will fail during the diversion?" I thought that the chances of a double engine failure must be so small that its not worth considering. But then I realized that the disguised question is, how separate are the systems for each engine? If the first engine failure is due to a bird strike, logically the second engine should have no greater chance of a failure. But if the bird damages a common fuel pump for both engines that causes the fuel pressure in the second engine to drop, then that engine might have trouble staying "lit" for lack of a better work. Thus, the more interdependent the engines are on common systems, the greater the chance that there will be a double engine failure. Modern airliners usually have at least double system redundancy, with the most crucial systems such as the hydraulic and fuel pumps, electrical generators, and FADECs having triple or quadruple redundancy.

Why are ETOPS ratings so important?

Taken from a customer prospective, the first reason is quite obvious: ETOPS helps ensure safe operations on long-distance or remote routes. But the advent of high ETOPS ratings has greatly added to efficiency both in terms of money and time in the airline industry. Often the remoter routes (such as those that cross the oceans far from land and the Arctic circle routes) are shorter than there lower ETOPS rating counterparts. The more common example is the New York City to London route. Prior to ETOPS-90, all twin engine aircraft could not go straight to London or NYC, but instead had to arc close to Newfoundland, Greenland, and Iceland, in order to stay within 75 minutes (since they would be under ETOPS-75) of a diversion field. Instead, airlines would have to fly the more expensive and sometimes oversized (for the route demand) aircraft such as the L-1011 Tristar, DC-10/MD-11, or the classic B747. So since the creation of the ETOPS rating system by the FAA and the resulting efforts by most airlines to meet the standards for each optimized route, ticket prices and travel times have decreased.

Now that I've explained ETOPS ratings, I can move onto the existence of the A340, A330, and B777 and why the B777 was/is such a successful aircraft. But as I was putting my thoughts together to explain it all, I realized that it is more complicated than I thought since the obviousness of the answer to me is due to things I have probably incorrectly assumed are common knowledge. So I've decided to stop this post here so I can think about how I want to explain the A340, A330, and B777 question. If you would rather have a short summary answer and move on to something new, I can do that also. I realize that ETOPS is not exciting to read about, but I suppose its importance in the aviation universe is enough to justify this post... I hope. If you have any questions, just let me know.

Here We Go... the Dreaded Airbuses

Telling the difference between some Airbuses and Boeings can be a pain in the ass. Unlike Boeing, oftentimes Airbus modifies its original types into different variants that are noticeably distinctive, further complicating the task. But nevertheless I'll try to clarify how to tell these planes apart.

A380-800

The A380-800 is the largest commercial airliner in service and is easy to spot, although currently I believe the only airport in the U.S. where you can see them is LAX, since Quantas uses one on its Sydney-Los Angeles route. These are rare, since they have only been in production for a few years, take a lllonnngg time to manufacture, and are very expensive, normally keeping them out of the hands of the non-subsidized American carriers. How do you recognize it? Its the only full length double decker airliner in the world, its huge, and it has the big (ugly) forehead above the cockpit (unlike the 747 which has its cockpit on the second level). I saw this plane close up at the Paris Airshow and at DeGualle Airport and they are huge airplanes (they can hold over 800 people in high-density configuration!).

A340-200,-300,-500,-600

The variants aren't that important here, as they just involve newer components, higher MTOWs, longer ranges, and longer fuselages. This one is also easy: its the only four engine, singe decked widebody (besides the now extremely rare DC-8 that I may cover in another post). It is also extremely long (with the A340-600 currently holding the record for longest airliner, although the B747-800 will surpass it once its delivered hopefully later this year). The A340 has designed for long range in the late 1980s, with its competitor being the B777, which is a far more innovative and successful aircraft. If you wish to know what are the reasons behind the designs of the A340, B777, and A330, as well as why you will spot B777s taking off from Logan but not A340s, just let me know and I can make it the subject of another post.

A330-200,-300

The A330 was designed right after the A340 and they both feature a common fuselage and wing structure. Obviously, the big differences between the two aircraft are that the A330 is shorter and has only 2 engines. This one is a pain to figure out, considering it has common features with both the B767 and B777. Just for knowledges sake, the A330 is intended in both range and capacity to compete with the B767. In fact, I'll be honest and say that until I made this post, I had no idea how to tell the difference between the B767 and the A330. They both have similar engines, landing gear configurations, and fuselages. The A330 is slightly larger, but this can be hard to notice at a distance. First, the B767 has a more blunted nose than the A330. The only other "easily" recognizable difference is where the tail meets the fuselage in the front. Instead of meeting the fuselage at a sharp angle on both aircraft, the tail structure tapers forward a little bit. There are too differences between the taper on the A330 and B767. The A330s is more pronounced, i.e. larger, than the B767s. The A330s also begins to taper off at a harder angle than the B767, which has a curved taper. Heres a picture of the B767 to demonstrate:

Although in the pictures the differences may seem obvious, when actually plane spotting its very difficult to tell. The similarity between the A330s and B777s nose shapes don't help either.

A320, A318, A19, A321

Okay, this plane is a pain in the ass only because as you may have noticed, instead of making small variants (like A320-100,-200,-300), Airbus made larger variations that are their own types. But the A320 is the original aircraft and by far the most widespread. The A320 is designed to compete with the B737 in the short-haul market, and is second only to the B737 in airliner sales of any type (yeah Boeing!). The A320 is actually quite easy to spot when compared to the B737, since the nose below the cockpit juts out distinctively and has a different cockpit window style to the B737, which you can see in the B737 photo in the previous post. Also, whereas the B737 is like a rotund corgie, the A320 is like a wiener dog. If you've taking a Jetblue flight greater than Roch-JFK or Roch-Logan, then chances are you've ridden a A320. Part of the reason Jetblue is such a successful low-cost carrier is because they only use two types of aircraft, the A320 and the Embraer ERJ-190, greatly lowering maintenance and training costs. Now, there is no point in trying to tell the difference between the A320,-18,-19,-21. But once again just to know, the numbers are relevant to length of the fuselage, i.e. capacity. The A318 is the smallest variant and the A321 is the largest. Not only are the size differences very small, but the appearances of and technology within the variants are virtually identical.

A300B1,-B2,-B4,-600, A310

The A300 is the first Airbus production model and dates back to the early 1970s. As a result, most of them have been retired, especially within the U.S., due to its outdated avionics and poor fuel consumption. This aircraft is famous for being the first twin engine widebody airliner, a market that Boeing jumped on and eventually dominated with the B767 and B777. You can tell it apart from any Boeings using the same characteristics as the A330. The challenge is how the hell to tell it apart from the A330. The A330 incorporated design features of the A300, as they both were targeted at the same niche. Since most of the active A300s have updated engines, you can't really tell between the two using the turbofans. Furthermore, the A330 is less than 10 meters longer than the A300. Instead of trying to find a tiny difference between them, I'll just help you tell the difference using context. The A300 is an old aircraft that has not been updated in many years by Airbus (unlike the older B747). In turn, usually only second-rate carriers that lease older, used aircraft operate them. The A330, on the other hand, is a modern aircraft that has been kept up with recent technological innovations. A330s are "widely" operated, used by carriers such as Delta (I used the ""s because as in all classes, Boeing aircraft are most widely used, if only by a small margin). In fact, one of Delta's A330s was the plane flying from Amsterdam to Detroit when the attempted Christmas bombing occurred last year. Finally, as for the variants, the A300B1 was the test version, the A300B2 was the initial production version, and A300B4 was the most produced model, and the A300-600 was a greatly upgraded version that eliminated the need for a flight engineer. Finally, the A310 is just a shortened version of the A300B4.

Yay! We've finished the Airbuses. The remaining aircraft are the Bombardiers, Embraers, and McDonnell-Douglases, which as there are few types, I can cover in one post. Perhaps one day I can also do a vintage aircraft edition, but probably not for a while.