S-3 Viking Flight Quality Improvement Program

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Lockheed S-3 Viking

The Lockheed S-3 Viking was a carrier borne antisubmarine aircraft that entered service with the US Navy 1974 and ended it’s front line service in 2009.

The War Hoover (as it’s known due to the sound of it’s engines) was one the few carrier borne aircraft from Lockheed and as such they partnered with Ling-Temco-Vought (LTV) who had a long line of success of building carrier based aircraft. Lockheed put LTV’s experience in the S-3 to work as it uses the main landing gear from the F-8/A-7 stable of Vought carrier based aircraft.

Before all naval aircraft enter service they all undergo testing to evaluate how they handle when coming aboard the carrier for landing and how they behave when launched from the carrier’s catapult. The testing for the S-3, conducted in 1973 was no different. The case study of the S-3 illustrates the design complexity that all naval aircraft undergo to safely operate from the carrier environment.

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Vikings from VS-21 “Fighting Redtails” aboard an aircraft carrier. Note the wing fold for stowage aboard the carrier.

The S-3 has a high aspect ratio wing the aircraft makes for a good glider and large turbofan engines that have 22:11 bypass ratio big that don’t respond to power changes quickly. Now you have an aircraft that uses low engine power to maintain position on the glide slope (with very low RPM on the engines). Not a huge problem on land but on a ship:

“If all the sudden your starting a settle coming into the carrier, you add power” to regain altitude, but nothing happens because of the delay in getting the engines to respond. “Then you find yourself sitting there looking at the ramp,” the wall of steel below the deck of the carrier. Hitting the ramp means dying. “In fact I almost hit the ramp” when testing the S-3 on the carrier, Webb said. “The combination of a very clean and very slow power response was a major problem.”

S-3 Viking 9.5 Engines

An S-3B illustrates how the engines are tilted 9.5 degress from the aircraft longitudinal axis.

Another problem was the S-3 would pitch up when power was added and pitch down when power was reduced. This was because the thrust line of the engines was below the center of gravity of the aircraft. This always placed the aircraft “out of trim” whenever a change to power was made. The remaining problem was that during simulation, Lockheed didn’t account for the burble of air coming from island and flowing across the landing area. Lockheed assumed the flow was horizontal behind the carrier.

“This gust responsiveness makes it considerably more difficult to bring aboard under wind conditions which create a strong ‘burble’ of distrubed air behind the carrier. In fact the aircraft failed its initial carrier suitability testing largely due to its gust responsiveness”

After additional flight testing, Lockheed implemented a number fixes to address these problems. The first was called “thrust trim compensation.” Whenever the pilot increased or decreased power, the elevators would automatically down or up to neutralize the pitching. “With that fix, a pilot trying to stay on glide slope while coming in to trap “does not have to fight the pitch with power all the time.””

Viking Pitch Trim System

The S-3 Viking’s Pitch Trim System as schemtically illustrated from the S-3 NATOPS Manual.

Another fix was applied to the S-3 spoilers. A spoilers is a control surface at the top of the wing, hinged on the wing’s leading edge. The spoiler is designed to disrupt or “spoil” the airflow on the top of the wing to dump lift. Normally, in the S-3, the spoilers are activated one wing at a time with movement of the stick left or right to assist the ailerons in control of the aircraft’s roll. With the press of a button the spoilers on the S-3 rise on both wings simultaneously. This allowed the pilot to reduce lift and descend faster without the pilot having to pull back on the throttles to reduce power. This “direct lift control” meant that the pilot could keep the engines at a relatively high power and not back to the unsafe “low-rpm” low power regime. The pilot needs the engines to main at a high power level in case he needs go around and try for another landing.

Viking DLC

An S-3 on launch from a carrier. You can see the DLC spoilers on the upper surface of the wings just forward of the flaps (seen in red and captured mid retraction).

These improvements took almost 10 years to apply and were collectively known as the FQIP (Flight Quality Improvement Program) Mod. The S-3 eventually became a very successful carrier borne aircraft and had a reputation the fleet as being an aircraft with relatively benign carrier landing characteristics. The Viking FQIP is one of many example of the performence constraints that naval aircraft must operate in.

S-3 Viking on the landing rollout after catching a wire.

S-3 Viking on the landing rollout after catching a wire.

Sources:

Flying the Edge by George C Wilson.

World Airpower Journal Volume 34 Autumn/Falll 1998.

S-3 Viking NATOPS.

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Army Chow- Just in time for the holidays

Old AF Sarge has a post up at his place musing over the best and worst of dining in an Air Force chow hall.

Meals in basic training were…. rapid. You didn’t have time to taste them. But the burping the rest of the day let you know what it was you had wolfed down. Not bad meals. Just not really a great environment to enjoy them. We did have Thanksgiving during my cycle, and my mom and an aunt and uncle were able to join me.  As usual, the Army does a fine job of putting on a traditional turkey dinner.

My unit mess in Hawaii seemed to be… poorly staffed. Breakfast was always good. It’s pretty identical throughout the Army. But lunch and dinner, while occasionally good, were usually just serviceable.

I was on three different posts in Germany. The first was excellent, the second was very good, and I simply cannot recall the third. Seriously, I’m drawing a blank on where it was, or what it was like.

You see, about halfway through my tour in Germany, I was assigned as a driver for the brigade XO. And the XO doesn’t plan his day around my ability to eat in the mess hall. So onto BAS I went. I could eat in the mess hall when feasible. Or failing that, I was expected to eat on the economy. Even after I left that job, I simply stayed on BAS the rest of my time in the Army. I still ate in the mess hall often. I simply paid cash.

Worst mess hall experience? TDY to Fort Benning for a couple months. We were billeted well away from any mess hall. And the school hours precluded us from actually eating in a mess hall. But the byzantine regulations that cover feeding and pay said that technically a mess hall was available, so we didn’t get any extra money. BAS hardly covers eating out for an entire month. There was at least a decent food court near our billets. For lunch, the instructors for the course set up a grill and made burgers for a buck a pop. Two or three burgers, and a quick trip to the vending machine for a couple bottles of YooHoo! were lunch.

Not exactly a mess hall, but ABN-AMRO/LaSalle Bank in Chicago had a cafeteria in the basement of their offices. And it was fantastic. And the members cafeteria of the Chicago Board Options Exchange had a monthly prime rib for about $7. A slap of nearly raw beef the size of a dinner plate! 

What’s your fond memories? Good mess halls? Bad college meal plans?

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Ferguson

Everyone else is talking about it, so here’s a couple random thoughts.

You’ll hear people lament that Michael Brown didn’t deserve to die for his crimes. Deserve? No. But the evidence shows that he took actions that led almost inevitably to his death.

There’s a tendency among males, especially young males, and most markedly among black urban young males, to escalate a confrontation. When that involves the police, that often ends badly for the police. But it almost always ends badly for the young man.

Brown wasn’t killed for stealing cigarillos, or jaywalking. He was killed because he placed a police officer in danger. Just being unarmed doesn’t mean there’s not a  potentially deadly threat. Don’t believe me? Allow me to introduce you to WorldStar HipHop (NSFW).

What the heck took the Guard so long to show up last night? It’s not like everyone didn’t know rioting was going to break out.

From the Conservative Wahoo:

 Those of us sitting in our comfy places watching and tut-tutting probably don’t understand deeply enough the mistrust that exists between a good bit of the black community and police forces.  I’ll wager that if we were to get some of these hooligans to sit down and present them with the evidence, they might even come to the same conclusion as the grand jury–but their reactions would still be the same.  This isn’t necessarily about Brown’s death, it is about perceptions built up over years and simmering rage.  The Ferguson incident simply provides a convenient outlet for these emotions.

Emphasis mine. Concur.

If you want to tell me there is a problem with how the police and the black community in America intersect, I’m all ears. But the Brown case isn’t the mountain to plant your flag on. Why is it that those who seek to incite their community to outrage always seem to chose a losing case? It can’t be that hard to find a case where a shooting was pretty clearly uncalled for. Heck, just ask Radley Balko.  The guy makes a career out of trying to highlight unjustified use of force by the police.

Or take a look at this shooting in NYC.

Could it be that certain instigators don’t wish for justice, but rather thrive on the unrest?

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One of the Greatest NFL Commercialz Eva

I am a fan of the New England Patriots, and as such I seem to be required to hate all things Manning.  Not a chance.  Not only is Peyton Manning one hell of a quarterback (his brother is no slouch, either), but I loved his old man, Archie in the long-ago days when he QB’d the Saints.

One of the things I like best about the Manning clan is their collective senses of humor.   They have had some great commercials (the one in the museum when the old man gives them the look for misbehaving being among my favorites) and Peyton certainly was a hit hosting Saturday Night Live.  But I think my favorite commercial they ever did is this one:

Makes you wanna go out and get football on your phone.  Yo.  Fo’ shizzle.

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Bastogne, as you’ve never seen it before.

Even the most casual of historians know that the sleepy little village of Bastogne became the center of attention during the Battle of the Bulge in December of 1944.

The First Division Museum in Catigny has an exhibit commemorating the battle opening tomorrow. In Lego!

Photo: Construction of the #lego Battle of the Bulge is underway! See it tomorrow through the end of 2014.

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Hagel out at DoD

So, word is current Secretary of Defense Chuck Hagel has submitted his resignation. Further, the rumor is he was pushed to resign.

Hagel doesn’t have much of a reputation as a bright light. Indeed, he’s really known as rather a dim bulb. One thing about the Obama administration. It’s incredibly partisan. And yet, it’s had a Republican as SecDef the whole time. That’s rather obviously an attempt to deflect criticism. The problem is, like so many other cabinet positions, it’s been neutered by the Obama inner circle and its “czars” and incredibly tight inner circle, which is basically Obama, Mrs. Obama, and Valerie Jarrett.

Rumored replacements for Hagel include Michele Flournoy or Ashton Carter.

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SECDEF Fired: Hagel Goes Under the Bus

Chuck Hagel

Big news this morning that Defense Secretary Chuck Hagel has been fired by President Obama.  Big news, but not surprising.  Hagel has openly contradicted the President several times, especially regarding the Administration’s rather childish assertions regarding the necessity of ground forces in the fight against ISIS.   You will hear various stories about how this was Hagel’s idea, and of course, the media will dutifully report as fact the White House’s version of events.  But that version will be as accurate and honest as WH proclamations on Benghazi, the IRS, Fast and Furious, ISIS intelligence failures, etc.

Though Hagel was not known as a deep thinker, the idea that he somehow couldn’t grasp the deeper and more complex defense issues smells like the intellectual elitism of the self-proclaimed far-left “ruling” class.  It is far more likely that Hagel attempted to keep Obama and his National Security Council grounded in reality, only to be poo-pooed and brushed aside by the overwhelming cacophony from the Marxist ideologues that have the President’s ample ears.   I was never a big Chuck Hagel fan, as he was a Global Zero guy whose viewpoints at various times bordered on the curious, but as SECDEF I thought he was one of the few at the top of the Defense structure with the spine to stand up to the rampant amateurish stupidity that emanated from 1600 Pennsylvania.  We could have done far worse.  We certainly might going forward.

Whether talks were “initiated” by Hagel or not, the nature of those talks were probably discussions about whether Obama was going to keep tossing aside wise counsel or not in favor of the childlike and naive rantings of his fellow-travelers.  And, the answer today seems to be a resounding YES.  Obama will continue to march forward in secular progressive lockstep to the Internationale, wreaking the concomitant damage on US security, foreign relations, and national power.

Funny that the Secretary of Defense that HE chose, to replace another that had had enough (Panetta), is now thought not to be up to the job.  One has to wonder who is.  Michele Flournoy has been mentioned, along with Ash Carter.  One has to think Bob Work is in the mix.  All are far too talented to want to serve out the last two years of the military train wreck that is the Defense Department under Obama.   It is like being hired to coach the Washington Generals, and being told you are expected to win.

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