Flying On Instruments-Part 1

This is the first in a series telling “all” about flying on instruments. I have written about flying IFR (instrument flight rules), and decision making etc., but not led you through all the nitty gritty. This first part will deal with the basic instruments and radios used.

Regardless of the type of IFR weather, there are certain basics that will always apply. Some of these conditions also must be followed in VFR flight as well. In order to achieve flight, a certain airspeed, as shown on the air speed indicator must be attained. Things that affect necessary air speeds include: temperature, aircraft weight, and flight conditions such as: turbulence, ice etc. Failure to achieve or maintain necessary
speeds may mean inadvertent stall e.g.(recent case in Buffalo). If certain speeds are exceeded however, as in an uncontrolled dive, the plane may disintegrate in mid-air. This maximum safe speed (VNE), is indicated on the air speed indicator with a red line. Prior to that there is a caution zone outlined in yellow. The safe zone is “in the green”.

The airplane attitude (position relative to the horizontal) must be kept within certain reasonable limits. This is done with the aid of info from the artificial horizon, perhaps the most important gage of the instrument flight array. This instrument gives a pictorial image of the plane’s flight with respect to bank angle and pitch (climb or descent). Turns generally shouldn’t involve more than a 30 degree bank angle. Recently a tragic crash occurred near Charlotte with bank angles achieved greater than 60 degrees. These are ok during certain maneuvers but never during instrument flight. Severe bank angles markedly increase stall speeds that may lead to disaster. Similarly, climb and descent angles are limited to relatively small values. All is done in order to maintain positive, safe control of the airplane. Problems arise when for what ever reason, a pilot gets distracted, or is too busy to keep things within safe parameters. Accidents sometimes occur for example, when an inexperienced pilot suddenly encounters instrument conditions (loss of visual cues).

The final primary instrument I will discuss is the easiest to understand, the altimeter. It is nothing more than a barometer calibrated in feet or meters. Usually it can indicate differences of 20 feet and goes from below sea level (flying in a gorge out west) to many thousands of feet. Flying either VFR or IFR generally requires adhering to certain rules that specify what altitude may be flown. In controlled airspace, as for example round major airports definite altitudes will be assigned by controllers (ATC). Almost all IFR flights are conducted under direct ATC oversight, and will entail flying an assigned altitude. Failure to adhere to this altitude may be the set up for a collision, or at least the cause for a collision alert system to activate if present on the plane. All US airliners have these systems aboard.

Finally, a functioning VHF (very high frequency) aircraft radio, preferably two or more must be aboard, enabling the pilot to communicate with ATC. Navigation radios are necessary and are frequently part of the communication radios. Several different types are needed and will be discussed later. Also a transponder is required which allows ATC to positively identify the aircraft position and altitude (mode c). ATC assigns a specific code (four numbers) to each flight.

That’s enough to get started on. I’ll discuss the pilot’s interaction with the above in a subsequent article about a real flight.

Flying IFR With An Option

We are on final vectors to runway 17 at Iwannabeontheground airport. The weather is just awful. Visibility ½ mile in smoke, fog and haze with the possibility of a thunderstorm. Ceiling is 250 feet and lowering. Night time is approaching and we are flying a single engine plane. Doesn’t sound too good does it? How about adding that the ILS just went out and we are left with only the localizer, making this a non-precision approach, with no glideslope (much higher minimums). Fuel aboard is 1 plus 15 or 75 minutes. Maybe, just maybe enough to get an alternate field with better weather. Scary scenario? Yes, but one faced by many pilots everyday. Most make it, but not all.

Some things that can be done that make things much less risky. Perhaps the most important is to always leave yourself an out. An escape route or plan if you will. Instead of trying to land with the weather at minimums at airport A, plan on going to airport B that has a better weather outlook. Ok, it may be farther from your destination, but that’s the price you pay for added safety.

Years ago, I was flying a passenger to Wheeling, WV, in B-58 Baron. The flight from Burlington,Vt was to take about 3 to 31/2 hours. Fuel aboard was 5 hours. As we were approaching the Pittsburgh area things began to cloud up, literally. The weather at KHLG (near Wheeling) was so-so but forecast to get worse and be near minimums. That meant we might not be able to land, but would have to go to our alternate, which would have been Allegheny County Airport (KAGC). Flight time between the two only 30 to 40 minutes. Adding everything up though, if we missed at KHLG we might not have enough fuel to return to Allegheny and still have 45 minutes of fuel remaining. The latter is the rule. The other factor was that the weather in the Pitt area was forecast to go down as well, further complicating things. So, after discussing things with my passenger, we decided the prudent thing was to land at KAGC, and the passenger drive to his destination. Yes, I know, not the most convenient, but the safe and prudent thing to do. There were no complaints and all turned out well. Better certainly than if we had disregarded the weather progs and plowed ahead only to find the weather at KHLG as bad or worse than forecast. That can and does happen.

So, the old adage: an ounce of prevention is worth a pound of cure, may have some meaning here.

Fly safely, and do plan ahead. If not, you too may end up a statistic.

It Was Like Flying Into A Black Hole

Night flight is not everyone’s cup of tea, in fact, some pilots dread it. I can certainly understand why particularly in actual IMC conditions in a single engine plane. But if the conditions are right, good VFR, stars above, maybe a moon, it can be just beautiful. In the distance, airport beacons beam their greeting to the sometimes weary traveler. The twinkle of light from houses, and the stream of headlights appearing as a swarm of bees far below on otherwise unseen roads, all help make up this almost mystical experience. Another thing I miss is the friendly glow of all the cockpit instruments, reassuring at a time of relative isolation. So as long as the machinery keeps on purring, there is nothing particular to worry about. Or is there?

Well, for one, landing at night can be tricky if one doesn’t recognize certain differences from daytime flight. Depth perception is limited and can be misleading to the inexperienced pilot. For example, just before touching down for a landing, during the day one looks straight ahead judging height and distance without much difficulty. At night, with the loss of depth perception, one must use their peripheral vision as a judge of height above the runway. If you try and just stare at what appears to be the runway you may be in for a real bounce. By using peripheral vision as well as straight ahead vision for alignment, judgment of height is much improved. To help the pilot judge the correct approach angle on final, VASI (visual approach slope lights) are a big help. Strategically placed at the end of the runway, they appear red if too low, or white if too high. If one is on the 3 degree slope, the light is a mixture of red and white. In other words, a VFR glideslope. Of course there should be threshold lights, and depending on the size of the field, many others as well. If the field is uncontrolled, frequently one can set the brightness of the lighting system by clicking the unicom frequency appropriately.

I remember one flight into a small airport in southern Vermont, one very dark, moonless night. It was like flying into a black hole. Navigating to the airport was easy using VOR aids. The problem was that there were virtually no surrounding lights other than a couple of red beacons on towers on surrounding hills. Runway lights were minimal, on one side of the runway only. Thank goodness for the VASI. I would have made an ILS approach, except there wasn’t one available. Anyhow, I landed safely, and was glad when I reached the terminal area and could shut down the engines.

So, night owl or not. Make sure your eyes are night adapted, keep lighting low in the cockpit and enjoy the darkness.

It pains me to read of another crash

It pains me to read about another plane crash, with all occupants dead, and no explanation other than “pilot error”. The pilot, older, with many years in the cockpit, should have been able to avoid the crash. From what I gather, the landing was balked because the plane was too fast and possibly high for the 4000 foot runway. You just can’t force some planes down on the tarmac if they aren’t ready. The result if you try, is to bounce, possibly porpoise, even hit the prop, as happened here. And, oh no, just read of another landing accident in a similar plane with similar terrible results, several days later.

As I smoke my philosophical pipe, feet propped up, and reflect on things, I wonder why things happen as they do. Have we become complacent to the point of relying on things
rather than knowledge, inherent to what we are doing. Is basic aeronautical science too abstract for the average pilot these days? Are flight instructors too casual in their teachings? Do they put their students through the rugged paces needed to deal with those
unplanned events that can lead to serious trouble? I mean really, a pilot should be able to handle a balked landing with the adroit application of power, and then proceed to land the plane once stabilized, again at the proper speed and attitude. That, as compared to trying to force or slam the plane down on the runway, when it still has enough energy or speed to fly.

Now, in all fairness, some planes are more difficult to land than others. One of the newer fixed gear, speed demons can be difficult to land from what I read. I am of course thinking about the Cirrus. The recommended approach speed is 78kn (1.3 Vso*). That is considerably faster than a Cessna 172RG, a somewhat comparable plane. Slower, but still a notch above many. I used to fly one, and enjoyed it. Vso of the RG was 50kn, and 1.3Vso was then 65kn. Considerably slower than the high performing Cirrus. I am wondering if the pilots that are having problems landing that bird are just not ready. Maybe, and this is only my opinion, they should have more hours flying the lower performers, as the C172’s until they have more flying experience. Then transition to the next higher category. Much as what I did, moving into the light twin category from singles.

On a technical note. One must remember that the kinetic energy of a moving object is proportional to the square of velocity. Therefore, landing at Vso in a Cirrus has 1.44 the energy to dissipate as compared to the Cessna 172 also at Vso. In a crash then, or in an emergency braking situation, there is almost 50% more energy to deal with at the higher speed. That can be a problem.

So, in summary. Getting there fast is nice, but really not all that important in the scheme of things. Rather, just lean back and enjoy the process, no matter how long it takes. When you reflect on your flying experiences, years later, you will remember the process, not how long it took.

*Vso- Stall speed in the landing configuration

If you want to be cool, fly a J-3

It is so hot out that I think the tires of all the airplanes I flew in would melt into a huge black goo. Just been thinking of flying in the heat of summer, and how the coolest and most fun flights were in a J-3 out of Tew-Mac airport. Tew-Mac (B09), was in Tewksbury, Mass., northwest of Boston, and closed in 1997. It was a paved 1850 ft runway heading 3-21. Now converted to condos, the only flyers have feathers.

My flight would begin by doing a quick walk around the plane, including checking the fuel in the gas tank in front of the cockpit, oil and a quick kick of the tires. If alone, I would tie the tail down and proceed to hand prop the engine. It would usually start at the first pull or two. Quickly retard the throttle and untie the tail hook. Hop in to the rear seat if alone, put on the seat belt, feet on the brakes and ready to taxi.

What made it so wonderful to fly in the warm weather was the ability to fly with the side panels open. There were two, one to open up, the other down. Once the challenge of taxiing was over and the throttle advanced, I was airborne in seconds. Stepping hard on the right rudder and some back pressure on the stick was all that was required.

Once airborne, flying at about 65 knots and 500 to 1000 feet altitude one was able to look at the world below as if in a balloon rather than a plane. Slow and peaceful, almost dream like, the delightful, cool air gushing over me. So much better than flying in the tight, stuffy, un-air conditioned cockpits of the newer, faster planes. With a slight headwind, the cars moving on I-93 beneath me were moving faster than me. But that was ok, I wasn’t in a rush.

Some of the real fun was flying at a few hundred feet above the ground, over unpopulated areas, free as a bird and barely faster. The feeling of freedom was unparalleled. It was a stark contrast to the controlled airspace of today. I didn’t even have a radio, as there was no electrical system. No lights either so night flying was out. Navigating was with a map laid across my lap and my eyes scanning for landmarks. The bouncing compass was some help, but tricky to interpret.

I learned a lot about flying with the J-3. Any change in power or attitude required some input on the controls. The auto-pilot was me. The side slip was standard on final as there were no flaps to increase the rate of descent. All that said, it was a dream to fly. Noisy but forgiving. I know, as I soloed in the bird.

My first long cross country was humbling. I was heading west to Fitchburg. I thought I knew just where I was. But after flying for about 45 minutes I wasn’t so sure. Finally I spotted an airport ahead and lined up on the runway and landed after clearing myself visually. After taxing to the ramp and shutting down I walked in to the FBO and found out I wasn’t in Fitchburg but Leominster. Ahem, the effects of a crosswind were impressed on my brain then. Then a nice flight back, to the correct field.

When it was time to land, I had to review effects of cross wind and avoid hitting any planes parked just off the narrow runway. A short taxi back to the tie down and it was over for the day.
Ah yes, those were the good old days.

Stay cool and fly right.

Gear Problems Revisited

As gear problems continue to frequent the accident sites, I thought a brief discussion of landing with a failed nose gear would be of interest.

I just read about a Beech C90 that had a gear problem that resulted in a landing only on the mains. The nose gear mechanism failed, but the mains could be cranked down. Another gear failure with a similar result involved a C-177. It was reported that the plane had a gear malfunction indication, and upon landing the nose wheel failed.

As I thought about these two partial gear failures, and the resultant damage to props, engines, fuselage etc., I thought how damage could be minimized in the case of the single. Yup, you guessed it. Once you can identify that only the nose gear is involved, which may be easier said than done, land the plane as a glider. That means shut the engine off on short final, indexing the prop to horizontal with the starter. Land on the mains, keeping the wheel back until the plane stops and finally noses over. This would prevent damaging prop and engine, assuming one doesn’t stall it in. The latter can be avoided by carefully monitoring your airspeed. Not a procedure recommended for twins unless your last name begins with an S.

Regardless of the gear malfunction, it would be a good idea to do a flyby over the airport where a reliable observer is available. Tower operators usually will cooperate in this regard, weather and traffic permitting.

Remember, look for the gear down lights on final and before. Otherwise you may not “have a nice day”.

Happy and safe flying.

Some reminders to help you have a safe Memorial Day Weekend

Rather than deal with just one area of concern, I am going to explore and revisit several topics. My first subject is timely, as lately there have been several bad crashes involving runway overruns. Last December I covered some of the things a pilot must consider as they line up on final approach or before.

For the non professional, the main consideration is runway length. The other physical consideration is whether obstructions are present, either on the approach or the departure end. Wind, rain, ice etc. must be taken into account as they affect stopping distance. Wind is perhaps the most common problem encountered. One must add 10% for required landing distance for each 2 knots of tailwind, up to 10 knots. So, a tailwind will significantly increase the amount of runway needed for a landing. Therefore, before lining up on final at your favorite strip, decide whether the weather conditions will allow you to safely land. Don’t forget to have a spot on the runway picked out to make your go around decision in a timely manner. A late decision may mean ending up in the woods or worse.

The recent unfortunate death of a jogger on Hilton Head prompted me to reflect on some training maneuvers I did years ago while on final approach to short runways. The sideslip is a very useful cross control maneuver to lose altitude quickly. I remember well, being able to look out the pilots side window at what lay beneath and ahead as the plane was skewed around because of the slip. That would come in handy if the windshield became obscured, as was the case in the recent mishap.

I still wonder at the number of wheel up landings that are cited on the FAA accident lists. It is so avoidable if one just adopts a routine before and while landing. On April 10, 2009, I wrote about just this, in “Three In The Green Or Else”. A more technical article discussing gear problems was written on March 31, 2010. The main thing to do is to adopt a check procedure that can be used in almost all situations. By saying to yourself, either silently or out loud, something as: three in the green, or down and locked, after checking the lights, you can save yourself from a gear up landing. No lights, time to review your emergency procedures.

Well, that’s it for now. A few words to the wise on some old topics: runway length, forgetting to lower the gear, and what to do if you can’t see out of your windshield.

Have a happy and safe Memorial Day.