Tuesday, July 08, 2014

Old School / New School

I’ve been flying the Mad Dog on the line for about five weeks now, have finished IOE, am on my third week of reserve, and have about 90 hours in the airplane. I wouldn’t say I’m comfortable yet – that’s going to take some time – but it’s getting more natural, I’m not having to make such a conscious effort to think ahead, I’m making fewer mistakes, and I’m up to about 90% of the speed of an experienced FO. It takes time to get used to any new airliner, but probably more than most in the Mad Dog, simply because it’s such a quirky, busy airplane. The good news is that the quickest way to get used to any airplane is to fly a lot of cycles in a short amount of time, and I’m certainly doing that.

The Mad Dog is basically a late 1980s stretch and update to a 1960s design. It is a contemporary of both the Boeing 757 and the Airbus A320, two much better designs in many respects. Perhaps a better comparison is the B737, another continually stretched and updated 1960s airplane that is not as good as it should be because Boeing maintained commonality with the earlier design. The Mad Dog’s builder was notorious for their thriftiness, reuse of existing components, and leaving as much of their designs unchanged as possible. The Mad Dog actually uses the exact same knob for its cockpit window latches as was used on the DC-3 (and -4, -6, and -7) throttle levers! Less humorously, the largest Mad Dog variant weighs in at up to 168,000 lbs MGTOW and uses the same basic wing as much smaller predecessors.

This lack of wing is the airplane’s most notable shortcoming. Its clean stall speed is quite high, which combined with takeoff warning system malfunctions has resulted in several bad accidents when crews forgot to set flaps for takeoff. After takeoff, we are limited to 15 degrees of bank until reaching a clean maneuvering speed of 250 kts or more at high weights; if a tighter turn is called for, we have to leave the slats out until maneuvering is complete. At altitude, one has to pay very close attention to airspeed, as it’s easy to get behind the power curve and be forced to descend to avoid stalling. Consequently the airplane is quite altitude-limited; it’s common to have an initial cruise altitude of FL300 or lower, a real handicap in thunderstorm season. The B737 comparison holds up here, as the newest super-stretch versions of that design are similarly limited.

In the cockpit, the Mad Dog kept many of the quirks of the original. Several systems retain manual controls and switches where competitors automated them – the pneumatic crossfeed valves, for example, or the fuel system, or engine ignition. The engine start valves are manual and must be continuously held throughout the start, making that a three-limb exercise in which the poor FO begs the Captain to taxi slower lest a pothole dislodge his finger and prompt an aborted start. The engines have no FADEC and care must be taken to avoid an overtemp or overspeed. The spoiler and flap handles are Rube Goldberg devices (held over from the original) that take practice to activate without a struggle. The whiskey compass is famously (and hilariously) mounted on the aft cockpit bulkhead, requiring a light switch and a glareshield mirror adjusted to look through another mirror in order to read it! There’s no way the FAA would certify such an arrangement on a new design, but because somebody gave the OK in 1965, the cockamamie arrangement lives on even in the Mad Dog’s younger cousin, the Angry Pup.

For all that, this is an airplane that has glass, dual FMS, autothrottles, autoland, and even VNAV. It’s all these new-school gizmos, combined with the retention of old-school systems, that make the Mad Dog so much busier than its simpler predecessors.  There's also the fact that these features represented early efforts in automation, as conceived by Long Beach - consider them an alternative vision of a future that never was. So we have glass, but the engine display shows the exact same round engine dials as the non-glass airplane, and the PFD just displays an attitude indicator; airspeed and altitude still have their own round-dial analog gauges. There’s a Flight Mode Annunciator, but it’s mounted inboard of the flight instruments, out of the pilot’s direct view despite being absolutely critical to keep in one’s scan. The autothrottles are laggy and flaky and occasionally command huge splits. The autopilot has two speed windows depending on which pitch mode you’re in, and reversion to another mode will also cause reversion to another speed if you’ve failed to keep the inactive window updated. The dual Honeywell FMS is surprisingly modern and capable (it's actually fairly similar to the JungleBus’ FMS) but since the airplane doesn’t have GPS, we can’t do RNAV approaches and frequently monitor raw data (the box determines its position through IRS/DME/DME inputs). The VNAV is unnecessarily complicated while being rather opaque and often unreliable, requiring very close attention to make sure it’s doing what you think it should be doing. That’s a pretty good description of the whole plane, really. It demands a lot of attention.

From this description you might think I dislike the Mad Dog, and nothing could be further from the truth. I’m having a blast! It’s so utterly unlike the JungleBus, and that’s 90% of the fun. The JungleBus would lull you to sleep if you let it; that’s never a threat in the Mad Dog. The plane is built like the proverbial brick shithouse. Flap and gear speeds are ludicrously high (Flaps 11 at 280 kts, Flaps 40 at 200) so there’s seldom any danger of being caught high. The engines are the penultimate -219 variant of the venerable JT8D, and are pretty reliable for an old design. Systems, though they lack automation, are extremely simple and robust. The controls are virtually foolproof (with proper maintenance; see Alaska 261); fly-by-wire in this plane means 3/8” stainless steel cables connecting the control columns to control tabs on each flying surface. The controls aren’t sporty by any means (those are pretty small tabs that you’re moving!), but the plane flies so solidly that it doesn’t really matter. It just sorta stays where you put it – kinda like the Piper Lance of my freight-dogging days, now that I think about it. The cockpit is extremely quiet, thanks to the rear-mounted engines. The seats are pretty comfortable. There are some neat unique features, like the takeoff condition computer to verify your takeoff trim setting and the dial-a-flap detent for optimized-performance takeoff configurations and get-down-quick descent settings. There are something like 30 different rheostats for ultimate night cockpit customization; I’m still figuring out which does what. Yeah, so cockpit trim pieces are always falling in my lap and the windows leaks on me every time it rains. It builds character! My airline is 100% sold on the Mad Dog’s financial performance and it seems they’ll be in the fleet for a long time to come. If the Mad Dog is going to be my upgrade airplane, I’m glad to be getting experience in it as an FO.

It’s worth noting that my airline actually has two Mad Dog variants. I'll call the newer one the Big Dog, as it seats 11 more passengers. It also has high-bypass turbofans with electronic engine control, more automated systems, and a hydraulic elevator that improves control responsiveness. Over the last couple years my airline has greatly expanded the Big Dog fleet, buying every used copy they could get their hands on; there are now roughly half as many Big Dogs as Mad Dogs. One of our largest competitors was until recently the world’s largest operator of Mad Dogs, though they call them by another name. Their variant is the exact same as ours, except they lack our quasi-glass cockpit. Our version has a different designator only because my airline insisted on it when they ordered them. Alas, the competition is rapidly forsaking their Mad Dog roots for the electric charms of the A320, making my airline the world's new Mad Dog king (especially if you count the Angry Pup, of which we're getting 88). Lots of Mad Dog FOs are moving to other airframes or to the left seat, making the Mad Dog a very common first airplane for new hires, and affording me nearly instant seniority in our junior New York base. I'll write about commuting to work there in my next post.

10 comments:

Tom B. said...

Sam,
GREAT post! I've always wondered about the idiosyncracies of the mad dog. I also found the flight characteristics and comparisons with other airframes fascinating. Reminded me of a recent strip in a stretched 737NG; the take off roll on a hot/humid day with a very heavy weight took for-ever, to the point where towards the end before rotation the thought crossed my mind that we were going to go off the end of the runway (it was about a 40-45 second take off roll). I've heard the 73NG's have very high landing and stall speeds too. I wonder, does this also affect the A321?

Really looking forward to reading more about mad dog flying. As a pilot, these intricacies you mention are really interesting.

Tom B. said...

I should say "recent trip" in a 737NG, not "recent strip" :)

Colin said...

"(just lube that jackscrew, Alaska)"

I assume this is a reference to the loss of 85 lives off the coast of California in January 2000. I cannot recall having ever seen a flippant remark like this in your writing before and chalk it up to the isolation of the schoolhouse, the cramming of so many manual pages. Feel free to delete this comment, but I would suggest an edit there.

Anonymous said...

Hi Sam,

Roger the comment above re Alaska; I figured I was mis-remembering the incident.

In any case, fascinating post! It's interesting to read how your employer insists on making money "the old fashioned way" via the 'Dog, and I can see how its characteristics keep you more "in the game" as a pilot.

By any chance, does the "pup"'s type end in a "Seattle 7"?

Keep 'em coming!

Marty

Sam Weigel said...

Colin--

You're 100% correct, it was a flippant and insensitive reference to the tragedy of Alaska 261, and I've edited the remark to something more respectful and useful (there's a link to read up on the accident & how improper maintenance caused the jackscrew to fail). My apologies for the insensitivity; I know there are a lot of people at AS & QX that lost friends & family in that accident.

Sam Weigel said...

Marty-- With only 3 legacy airlines soon to be remaining, I'm not going to be able to hide my employer from anyone with a little industry knowledge, but am at least keeping a veneer of anonymity for the general public by using aircraft nicknames, etc. You are correct that the Angry Pup's designator changed after its builder merged with another aircraft company. It's a really well-done airplane, incidentally, a nearly clean-sheet redesign of the DC-9-30 along the lines of what Boeing *should* have done with the 737NG.

Tom B. said...

Sam,
do the high stall speeds and performance issues you describe in the 737NG and stretched mad dog also affect the A321 in a similar way?

Speed said...

The aft bulkhead mirror was a carryover from the DC-8. I'd love to know why it was put there in the first place.

JetAviator7 said...

I have a lot of time in a Chieftan; owned one for a number of years (N600HF) Miss her a lot!

Be sure to protect your eyes whenever you take to the skies with a pair of randolph aviator sunglasses - they are the best!

Sam Weigel said...

Tom B-- Oops, meant to respond to this. Yes, when Dave @ FL390 was blogging I seem to recall him talking about the 321's dogginess, whereas the 319 is a total hot rod. I don't think it has the same tailstrike issues that the 739 has, at least, as it's higher off the ground and the flight control software theoretically should prevent tail strikes.

Speed-- I'm told that it was originally due to excessive magnetic interference from flight instruments & avionics. If true, that begs the question of what exactly other manufacturers did differently to shield their airplanes' glareshield mounted compasses!