#flaps my hands at maximum velocity

[feltcreature]

Would you guys still love me if i posted selfship .

[onlyjellyillputinmybelly]

JESUS F CHRIST MY HAPPY HAND FLAPPING HAS REACHED MAXIMUM VELOCITY

[hedwigstalons]

The Tracy Prize - part 19

A boring afternoon at work led to the creation of Claire, the rather grumpy and tech-phobic chemist.  I never expected the little fic she spawned to run to over 25k words.  I may also dig her out in future as there were other scenes that didn’t really fit this story.

 Thank you to everyone that came along for the ride.  Each like, reblog and comment was very much appreciated. @willow-salix thank you for digging me out of several plot holes.  And thanks to @gumnut-logic for opening the door and welcoming me in to this fandom, I probably wouldn’t have attempting writing Virg if it wasn’t you.

  So now…the final part.

Here are the earlier parts for those that want to go back to the beginning: part 1, part 2, part 3, part 4, part 5, part 6, part 7, part 8, part 9, part 10, part 11, part 12, part 13, part 14, part 15, part 16, part 17, part 18

xoxoxox

Claire sat on a bench in the locker room near the hangers, wrestling with a rust coloured boot.  After a determined tug her foot popped around the bend in the heel and she was able to close the seals around her calf.  

The synthetic fuel had been cleared for field testing.  She knew Virgil was already in the cockpit of Thunderbird Two, waiting for her to suit up.  She didn’t want to keep him waiting.  She was looking forward to spending some time with the engineer.

She wondered how her life had managed to take such a surprising change in direction. Just a few short months ago International Rescue was just a name that appeared in news reports.  Anonymous heroes who swooped to the rescue.  Now it meant a houseful of people who risked their lives on a daily basis to help whoever made the call.  People that she was proud to call her friends.  Her thoughts lingered on one particular operative that she wished was more than just a friend.

As she adjusted the prototype uniform she reflected on exactly how this particular development had come about.

It had been a difficult day for all of them.  One of those days when the tension in the villa thrummed like an over tightened guitar string.  One of those rare days when Scott had announced he was out of his depth and called for outside assistance over the comms.  He had made an error and needed help dealing with the fallout, both literally and figuratively.  It had fallen to Claire to guide him through the process of decontamination from the material that coated himself and his body cam, obscuring Claire’s view of the tools and substances at his disposal.  That coating had turned out to be lithium hydride, a tricky substance that had the tendency to spontaneously ignite in humid air.  It was a tense time as she talked the First Responder through the clean up procedures, all the while hoping he wasn’t about to catch fire.

When Scott had finally made it home some 20 hours later he looked distinctly older than when he had set out.  He had announced that perhaps there would be times when it would be useful to take the chemist out in the field to try and avoid these situations occurring in the first place.  Claire had been inclined to agree with him; if Scott had paused and consulted her before charging into the factory he would never have got coated in the volatile substance in the first place.

What followed was a whirlwind of sketches, concept design and finally the prototype uniform.  

A uniform that was currently highlighting its flaws and would definitely need a redesign.

She would gladly have gone on the test flight in her usual clothes but Scott has insisted that, since she had a uniform, she should wear it when going off-island on International Rescue business.

Claire gave up trying to get the zip on her back done up.  She picked up the helmet and rebreather kit that turned her uniform into a grade two certified hazmat suit and headed towards the hangers.

xoxoxox

Virgil looked up from his pre-flight systems checks as Claire entered the cockpit. Technically he could have taken this test flight alone but he thought the chemist ought to get the chance to experience the result of her hard work first hand.  

If he was being completely honest he found himself seeking out opportunities to spend time alone with Claire.  He pushed those thoughts out of his mind.  Claire was dedicated to her work.  She seemed to enjoy his company but had given no indications that she was interested in him being anything more than a friend.  She was a professional to the core.

“I hope we won’t be needing those” he said, indicating the helmet and rebreather in her hands.

“You and me both, but Scott said to keep all the parts to hand.”

Virgil knew the sense in that.  You never knew what could happen when out on a mission and it paid to be prepared. His own helmet was close at hand.

“So how does it feel?  Does everything fit?”

His eyes raked up and down the petite form, currently clad in the ruddy tones that marked her out as one half of International Rescue’s scientific division. Of course it fitted perfectly. The full body scans taken as part of her medical had ensured that the garment was perfectly sculpted to her form.

He forced his eyes back to her face, hoping she hadn’t noticed his lingering gaze.

“Well the material is a little stiff.  I think the polymer coating is reducing its flexibility.  It also takes far too long to get on.  The biggest problem though is this.”

She spun around revealing the triangle of bare flesh at the top of her back.  

“If the main fastening stays at the back I’m going to have to get changed into uniform en-route so one of you others can buddy check my seals.  I just can’t reach it right.  Please can you finish doing me up?”

Virgil felt a lump form in his throat.

Claire held her ponytail out of the way so Virgil could finish closing the zip without snagging her hair.  A firm hand then ran slowly up her spine from base to neck, sealing shut the protective flap that covered the zip.  Claire’s body tingled in response.  Her mind wandered, imagining those same strong hands reversing the action later and freeing her from her uniform.  She gave herself a mental shake.  This was Virgil.  A colleague. It was…inappropriate.

Virgil returned to the pilot’s seat while Claire took the co-pilot’s side that was normally occupied by Gordon.  

This would be her first time being piloted by Virgil but not her first time flying in Thunderbird Two.  That first trip was tainted with bad memories.  Her first flight had been spent in worried silence.  Gordon at the controls.  Virgil in the med bay, out cold from the dart she had been responsible for shooting. She was still haunted by visions of Virgil crashing to the floor of the conference centre, the dart stuck in his chest.

The atmosphere in the cockpit today was excited rather then worried, but still serious.

The ability to control the Thunderbirds remotely meant that several test ignitions had been trailed but this would be the first true flight using the new fuel. The chance to test if reality lived up to expectations.

Virgil opened the comms link to both island control and Thunderbird Five.

“Pre-flight checks complete.  Everything responding as expected.  Thunderbird Two is ready for take off.”

“I’ll be keeping a running watch on your systems readouts and I’ll keep comms open,” John responded, his hologram floating above the control console.  “Stick to you pre-programmed route I’ve sent you. I’ve alerted the GDF that you are on manoeuvres so we can expect a call from Aunt Val later.”

“Why are the GDF involved?” Claire asked.

“Just common courtesy.  We give the GDF a rough flight plan and they alert any military operational in the area. It saves any cases of mistaken identity. We don’t want Two shot down again.” John replied.

Claire looked alarmed.

“That only happened the once, Johnny.”  Virgil had still never truly forgiven the US Navy for crippling his beautiful ‘bird.

“Yeah, well that was once too many.”

Scott’s voice cut in.  “If you two have quite finished…”

The rock wall disguising the hangar entrance lowered as Scott activated the mechanism from inside the villa.

Virgil taxied his Thunderbird out on to the launch pad.  The pad tilted upwards and the view from the cockpit changed from one of sea to one of sky.

Virgil directed power towards the thrusters.

An intense roar filled the cockpit.  Vibrations built up in intensity.  The mighty craft slid forwards and took to the skies.

“Thunderbird Two is go.”

xoxoxox

Virgil concentrated intently on the flight.  He had spent so many hours flying Thunderbird Two that he was fully attuned to her quirks and moods.  He felt each difference in response and behaviour without the need to check the instruments for confirmation.  The engine pitch was slightly lower.  The vibrations slightly stronger.  He tried a few turns and altitude adjustments and was pleased to see that Two responded just as well as before.

It was time to test her for speed.

Virgil eased the throttle forwards.  Scott’s voice came over the comms, reading out their velocity in increments.

“6,000 kilometres per hour.”

“6,500 kilometres per hour.”

“7,000 kilometres per hour.  Approaching previous top speed.”

Virgil continued to push the throttle.  He could feel that Two had more to give.

“8,000 kilometres per hour.”

“9,000 kilometres per hour.”

As each increment was read out the tone became excited.

“10,000 kilometres per hour.”

Claire looked across at Virgil.  A huge grin was plastered across his face at the raw power under his control.  It was as if Two was singing to him.  She hummed as he pushed the throttle to the maximum.

“!0,200 kilometre per hour” he whooped.  “Maximum throttle reached.  Easing off now and returning to base.”

“FAB Virgil.  See you back home soon.”

The pure delight Virgil was experiencing was evident.  He practically bounced as he guided the craft back over the Pacific Ocean. Their island home was soon visible again.

Virgil switched to VTOLs and brought them in to land.

xoxoxox

The two occupants of the cockpit grinned at each other, their eyes shining.  They were buoyed by the thrill of success.

Harnesses were released.

Claire found herself enveloped in one of Virgil’s bear hugs.  The air nearly crushed out of her body by his exuberance, her body held firmly against his chest.  She found herself returning the hug, wrapping her arms around his waist, burying herself in those powerful muscles.

“You did it!  You actually did it!”

Virgil was still riding the high of emotion.  Claire’s feet lifted off the floor in the engineer’s delight.  When she was placed back down she felt a kiss planted on the top of her head.

The pair of them both stilled and stiffened as the action registered.  

Claire looked up to meet warm brown eyes that looked ashamed, scared…hopeful?

Virgil cursed his lack of self-control.  In that one unguarded moment he had risked everything.  Claire had changed a lot since coming to the island but she could still be prickly on occasion.  Her flares of temper were becoming less frequent; there was more laughter, more enjoyment in being part of a team, but she had never invited him to cross this line.

Virgil braced himself for the backlash.

The backlash never came.

Their eyes remained locked.  Neither let go of the other.  Arms continued to encircle bodies pressed close together.

Claire found herself sinking into those chestnut depths.

Lips tentatively met, at first hesitant with the fear of rejection, then pressed more firmly as each explored the object of their secret desires.  Neither wanted to that moment to end.  Blue pressed against rust, the colour the only way of distinguishing the entwined bodies.

When they finally broke apart, eyes bright and cheeks flushed, Claire reflected that she might not have got the research grant but she had surely won the greatest Tracy prize of all.

-FIN-

[jacewilliams1]

Always read the fine print

The latest AOPA Air Safety Institute in-person seminar, “Peaks-to-Pavement… Applying Lessons from the Backcountry,” was a big hit. The crux of the seminar was emphasizing that if certain tactics, techniques, and procedures (TTPs) kept you safe while operating in challenging backcountry conditions, then they’d probably also serve you well in more benign frontcountry flying.

I’d like to share some of my observations; a sort of PIREP summary of what I encountered during my presentations in six states/13 cities. Some caveats: This was not a Bush Pilot 101 course. We made it clear that this wasn’t a comprehensive how-to on backcountry flying, and stressed that pilots should seek qualified instruction before flying in the backcountry.

We also pointed out that the concept of “backcountry” has more to do with the condition of an airstrip, than its actual geographic location. They don’t have to be isolated, one-way in/out, dirt strips, at 9,000 ft MSL in the Rocky Mountains. You can have an airstrip that exhibits a lot of backcountry traits (short/soft/rough, sloped, obstructed takeoff and departure paths, no weather info or services available, etc.), located within earshot of the drive-thru window at your local, sea-level, Burger King.

I always enjoy poking, good-naturedly, at pilots who own their airplanes. It’s my contention that pilots ought to know their planes intimately, and not just from a seat-of-the-pants, stick-and-rudder proficiency standpoint. They should know everything about their plane that is, in fact, critical to their safe, proper, and efficient operation. The most important information is readily available; it’s right there in the Pilot Operating Handbook, or Owner’s/Aircraft Flight Manual.

Read the POH – all of it.

It was pretty obvious that some folks hadn’t cracked open their respective book(s) in a long time. Those who had studied their documents, tended to be familiar with the BIG PRINT stuff, like their Normal Procedures sections and Emergency checklists, but were not so well-versed when it came to the various Notes, Warnings, and Cautions found throughout. There’s a lot of free, but hard-earned, wisdom in that fine print, all intended to protect life and limb.

When it came to aircraft performance-related issues, lots of folks either never, or at least rarely, applied the adjustments/corrections, as directed by the manufacturer.

It was also clear some pilots had been operating (successfully, since they’re still alive and kicking), mostly by using various combinations of ROTs (Rules of Thumb), WOM (Word of Mouth), TLAR (That Looks About Right), etc., and in some cases, the good ol’ WAG (Wild A** Guess)! Since that stuff worked for them so far, and nothing bad had happened yet, they saw no reason to change their behavior.

One of the key areas we focused on was short and/or soft field operations, and all the associated factors that can ambush you. I’d start this discussion with a trick question: “What’s the FAA definition of a short field?”

The answer, of course, is there isn’t one; the pilot decides what is short, and therefore it’s subjective. What may be short for someone flying an ancient Stinson 108 at max gross weight, may not be short for a guy in a featherweight Carbon Cub. Equally as important, what is short for you today, may not be short for you tomorrow (OK, maybe next week), based on your proficiency in short field ops.

Deciding what constitutes a soft field was a bit easier; we generally agreed that anything not paved was soft, although there are certainly some very hard, but unpaved, surfaces.

My next question: “What’s the effect of grass on takeoff and landing distances?”

Most would answer correctly that grass increases takeoff distances, including both ground run and distance to clear the proverbial 50 ft. obstacle. But, by how much made them pause: “It depends; is the grass tall or short, wet or dry?” was a typical, but correct, response.

The answer may, or may not, be found in the performance chart “Notes” section in your plane’s POH. Some aircraft manufacturers direct you to make very specific adjustments to the info you derive from their charts or tables. Others, not so much.

Cessna’s guidance varies from “…on a dry, grass runway, increase takeoff distances [both “ground run” and “total to clear 50 ft. obstacle”] by 7% of the ‘total to clear 50 ft. obstacle’ figure” (1973 Cessna 150 Owner’s Manual) to “…on a dry, grass runway, increase distances by 15% of the ‘ground roll’ figure“ (1976 Cessna Skyhawk Model 172M Pilot’s Operating Handbook.)

Having different correction factors for different airplanes makes sense, because they are different. The danger comes when you arbitrarily apply an adjustment from a previously-owned plane to the one you’re flying right now… and it doesn’t end well.

Beechcraft must not trust pilots to do math; they publish separate charts just for grass surfaces: e.g., “Normal Takeoff Distance-Grass Surface.” However, the really fine print in their Notes section says, “For each 100 pounds below 2750 lbs., reduce tabulated distance by 7% and takeoff speed by 1 mph” (Beechcraft Sierra 200 B24R Pilot’s Operating Handbook). Now that’s some precision flight planning guidance!

Grass can definitely reduce runway performance – but by how much?

By comparison, the Piper Cherokee 140B Owner’s Handbook only provides a vanilla “Take-off Distance vs. Density Altitude” chart, with no guidance on adjustments.

At the extreme end of the manufacturer’s takeoff guidance spectrum, the one POH for all Piper Super Cubs simply states, “Don’t worry about it.” (I’m kidding.)

When it came to landing, a fair number of pilots were adamant that grass decreases landing distances.

No, it doesn’t. At least according to the manufacturers. I got into several heated discussions with folks who swore (while demonstrating it with their hands) that they could drop it in, over a 50 ft. obstacle, plant it firmly, dump the flaps, slam on the brakes, and stop less than 100 feet past the threshold.

I’d like to think I could too, but, for example, the Notes section on the “Short Field Landing Distance at 2550 Pounds” chart for a 180 hp Cessna 172S unequivocally states: “For operation on dry grass, INCREASE distances by 45% of the ‘ground roll’ figure.”

When landing our Cessna 150, the POH guidance is: “For operation on a dry, grass runway, INCREASE distances (both ‘ground roll’ and ‘total to clear 50 ft. obstacle’) by 20% of the ‘total to clear 50 ft. obstacle’ figure.”

Piper doesn’t even address landing on anything other than a “Paved Level Dry Runway, No Wind, Maximum Braking, Short Field Effort,” with power “Off” and 40 degrees of flaps, so it’s up to you to figure out your own correction calculus for any other combination.

Other aircraft’s POHs direct different adjustments; but in all cases, if they address grass landings, they’ll tell you to increase the distances – regardless of your technique.

Of course, the manufacturer is taking into account all the science behind the landing kinetics; boring stuff like mass, inertia, friction coefficients, braking effectiveness on different surfaces, etc. We all believe that with our finely-honed pilot skills, we can do way better than what their data says. But when it comes down to Art vs. Science, the latter usually wins.

My next question: “What are the effects of slope on takeoff and landing distances?” Now, it got really interesting!

Since not all manufacturers address the impact of slope on their specific airplanes, you really must contemplate the guidance that is out there and evaluate the TTPs you’re comfortable with.

Some commonly accepted, generic ROTs for the effects of slope, include the following relationships: a 1% upslope will increase effective takeoff distance by 5%; a 5% upslope will increase effective takeoff distance by 25%. (Note: Don’t ask me to quote a single source; there’s lots of reputable ones out there, including Wolfgang Langewiesche.)

If you further adjust/pad these numbers, or interpolate for a slope somewhere between 1% and 5 %, or greater (yikes!), the math overwhelmingly supports the commonly accepted notion that you “always” takeoff downhill and “always” land uphill.

But “always” isn’t the same as “always, always, always…” because there are times when it may be prudent to do the opposite: takeoff uphill and land downhill. Two of the key variables being wind direction and velocity.

Always land uphill… right?

Understanding the impact wind has on takeoff and landing distances was another area folks seemed content to guess at, instead of applying specific POH guidance.

The Cessna 172S “Short Field Takeoff Distance at 2550 Pounds” chart Notes state: “Decrease distances 10% for each 9 knots headwind.” You could be confronted with a situation where the 5% increase in takeoff distance caused by a 1% upslope, is more than offset by the 10% decrease in distance afforded by a headwind.

Even more interesting, the Notes also add: “For operations with TAIL WINDS up to 10 knots, increase distances by 10% for each 2 knots.”

Although it is absolutely desirable that you always take off and land into the wind, you might not have that option. The manufacturer may provide the data you need to make a pragmatic decision regarding tailwind operations. The real question is: are you comfortable and competent enough to do it? Or the more appropriate question: should you? The best answer might be, “Wait for conditions to improve.”

All these discussions led nicely into the next topic that people tended to guess about, possibly at their peril: can I clear that obstacle off the end of the runway?

Obstacles aren’t always the natural kind (high terrain, tall trees, Bigfoot, etc.); some of the most dangerous ones are man-made (powerlines, towers, bridges, buildings, wind turbines) because we’ve gotten so used to seeing them, they’ve become innocuous. For our discussion, “Spiraling up over the airfield” wasn’t an option; we’ll talk about the impact of density altitude on aircraft performance in another segment.

The concept of flying an Obstacle Departure Procedure (ODP) doesn’t just apply to IFR operations.

The challenge is that ODPs require understanding climb gradient requirements versus rate of climb requirements, and how the two are related. The idea of flying a self-engineered ODP, if required, to escape from an obstructed environment, shouldn’t intimidate anyone – if they know how to do the math.

There are two key ingredients needed to design your own ODP. First, you must calculate your ground speed. Second, you must know how tall and how far away the obstacle is, so you can calculate the climb gradient required; i.e., how many feet per mile you’ve got to climb to clear it.

Since we don’t have climb gradient “Feet per Mile” gauges in our planes, we’ve got to come up with a performance metric we can use: our rate of climb in Feet per Minute.

You don’t need a formal departure procedure to do some basic climb math.

The math is simple: multiply your groundspeed (we’ll use 70 mph), by the climb gradient required (e.g., a mountain ridge, 800 ft. above field elevation, 2 miles away = 400 ft. per mile): 70 X 400 =28,000.

Take the “28,000” number, divide it by 60, and you’ve just come up with 467 feet per minute – the rate of climb required to clear the ridge. Having a vertical speed indicator is a bonus, but if you’re familiar enough with your plane’s performance, you shouldn’t need one.

The bottom line: don’t tempt fate. If you determine that you’ll need to generate a 467 foot-per-minute rate of climb, and on your best day, at sea level, your 65 hp Champ can barely wheeze at 200 feet per minute… don’t even bother starting the engine.

Note: if you want to err on the conservative/safe side, overestimate your groundspeed – that means you’ll be closing on the obstacle quicker and will require a higher rate of climb.

Of course, you can also just cheat and carry the descent/climb tables from a government approach plate book. They’ve done the math for you.

At the End of the Day

Depending on the make, model, and vintage of your airplane, there may not be any useful manufacturer guidance on performance computations. But understanding the basic concepts, like distances on grass increase, not decrease, is important. The exact adjustments required are going to depend on a lot of factors unique to your plane, your techniques, and the conditions. Don’t pick a random rule of thumb and apply it blindly to your circumstances. To paraphrase astronaut Matt Damon in The Martian, you need to “science the poop out of it,” before you’re past the point of no return.

Unfortunately, hope is not a strategy when it comes to flying safe, especially in backcountry conditions, where the margins for error are miniscule, and the consequences of small lapses in judgment, or errors in planning or execution, are usually catastrophic. So, please, always read the fine print.

The post Always read the fine print appeared first on Air Facts Journal.

from Engineering Blog https://airfactsjournal.com/2019/08/always-read-the-fine-print/