Troublesome Definitions

Hi Readers: In my aviation experience I've found that certain definitions (FAA regulations, for instance) - acronyms and phrases - indicate a definite meaning, but relate to several separate operations. Here is a beginning list, covering a few basics, and items relating pretty much to complete flight. There are other definitions that will be covered, periodically, in future blogs. In fact, most of them are covered in the Pilot/Controller Glossary of the Aeronautical Information Manual (AIM).
Basics:
Ceiling - Height of the lowest layer of clouds or obscuration phenomena that is reported as
broken, overcast, or as obscuration.
Visibility - In units of distance to see and identify prominent unlighted object by day and
lighted objects at night, in statute miles.
Track - The actual flight path of the aircraft over the surface of the earth.
Tailwind - Any wind greater than 90 degrees to the longitudinal axis (magnetic) of the
runway.
Crosswind Component - The wind component measured in knots at 90 degrees to the
longitudinal axis of the runway.
True Airspeed - Calibrated airspeed corrected for altitude and temperature. True airspeed
increases with altitude.
Cardinal Altitudes - Odd or even thousand-foot altitudes or flight levels.
Weather:
Significant Weather - SIGMETS - severe and extreme turbulence, severe icing, widespread
dust or sandstorm that will reduce visibility to less than 3 miles.
Marginal Weather - Less than VFR conditions.
Hazardous Weather - Summary of SIGMETS and PIREPS such as thunderstorms, low
ceilings and visibilities not included in Hazardous Advisories.
Climb and VFR Flight:
Cleared As Filed - Aircraft is cleared to proceed IAW the route of flight filed in a flight
plan - does not include the altitude, DP, or DP transition.
Climbout - That portion of flight between takeoff and the initial cruising altitude.
Climb To VFR - ATC authorization for an aircraft to climb to VFR conditions, within certain
class surface areas when the only weather limitation is restricted visibility
- must remain clear of clouds.
VFR Not Recommended - An advisory by a FSS to a pilot during preflight or an inflight
weather briefing - when current and forecast conditions are at
or below VFR minimums.
Visual Meteorological Conditions - Weather conditions in terms of visibility, distance from
clouds, and ceiling equal to or better than minimums.
Special VFR Conditions - Conditions that are less than for basic VFR - permitted flight
under VFR class surface areas.
Approach and Landing:
Visual Approach - On an IFR flight plan, which authorizes the pilot to proceed visually -
ceiling 1,000' and visibility 3 miles.
Contact Approach - By visual reference, on an IFR flight plan, only by request from the
pilot, and when the ground visibility is at least 1 mile.
Straight-In Approach - Can be either VFR or IFR - visually and clear of clouds.
Runway Threshold - Relates to runway markings for visual, precision, and nonprecision
approaches, including a displaced threshold.
Touchdown Zone - The first 3,000' of runway beginning at the threshold.
Terminal Area - A general term used to describe airspace in which Approach Control
provides service to airport traffic.
Thanks for listening. R.S.

What Is Marginal Weather?

Hi Readers: Marginal weather is a subject which has bugged pilots for years, and has been the cause of many aircraft accidents - many fatal. Airline pilots, if given marginal weather conditions, automatically expect IFR conditions to follow, and of course they file IFR flight plans anyway. To the GA pilot, marginal weather, depending on the pilot's ratings, experience, and proficiency, is a matter to be dealt with on an individual basis. Too often the GA pilot fools himself by deciding the weather, deteriorating, will get better ahead.
Unless we have divine powers or a degree in meteorology or Aerology, we should not attempt to outguess the weather. Let's let the weather man - briefer, forecaster, or whatever name he goes by, handle the weather for us, X-C or local flight. We should listen closely to his words and ask the routine and difficult questions. As pilots, however, that still does not absolve us of not knowing what VFR, marginal weather, and IFR are and their differences. And the flight, local or X-C, is ours to plan and execute safely.
So marginal weather conditions are somewhere between VFR and IFR - let's get specific.
The FAA defines the term as ceiling 1,000' to 3,000' (AGL), and visibility 3 to 5 miles - interpreted as flight visibility (How expert are we in estimating visibility?). So marginal weather is just beyond VFR and that's usually where the problems start. Unless we are IFR qualified, we should immediately question our ability to continue with our flight plan (if we have one) or alter our course and revise our flight plan. Let's ask ourselves, do we honestly believe, knowing our capabilities, that we should continue the flight.
The National Weather Service, and other weather facilities, stand ready to assist us in our preflight preparations and flight planning, but do not define marginal weather or make decisions with respect to marginal weather. There can be a briefing for the flight, a forecast for the route of flight, or weather advisories. Readily available is METAR, FA (Area forecasts which give MVFR (Marginal VFR) reports for areas of 3,000 Sq miles at any one time, SIGMETS (4 hour period), and AIRMETS (6 hour period). TIBS ( area and route briefings) can be used, but is not considered a substitute for briefings by a weather Specialist (Call 1-800-WX BRIEF). Then there is also AWOS (Automatic Weather Observing System) at most airports, transmitted on a discrete VHF radio frequency - these airports listed in the FAA Airport Facility Directory.
There is a fine line between VFR, MVFR, and IFR conditions due to weather phenomenon such as low-level, layered clouds (associated or not associated with weather fronts) changing ceilings and visibilities with the advent of fog, dust, or haze conditions, even to the point of sky obscuration.
Most aircraft accidents relating to low ceilings and visibilities (flying into marginal weather) are the result of somewhat inactive pilots who are not qualified for IFR flight and, more often than not, attempt flight by visual reference into deteriorating weather conditions. Losing the visual horizon, they are immediately at risk to experience vertigo. If flying by reference to instruments is not accomplished immediately, control of the aircraft may be lost. Continued flight into adverse weather (marginal conditions) is the single cause of the greatest number of fatal accidents.
The best advice is to be aware of, and on the alert for, weather phenomena that may produce marginal VFR and IFR conditions. Above all, pilots should be honest with respect to their capabilities. Can I handle this weather? If not, do a 180 degree turn or change course or altitude immediately - don't wait. Get back to VFR conditions. There will always be another time - perhaps additional proficiency time.
Thanks for listening. R.S.

2007 December Accidents/ incidents - Part II

Hi Readers: Continuing from Part I, there were 9 other fatal accidents and 4 nonfatal accidents (1 serious injury) in the December 2007 accounting. The first accident, a Beech A36 -3 fatal - appeared as a typical VFR, no flight plan, 391 nm X-C flight encountering IFR conditions, colliding with mountainous terrain at 7,000 feet near Minersville, Utah. The reported weather at Melford, Utah (5,039' msl) was visibility 13/4 miles in light snow, scattered clouds at 2,500', overcast at 3,000', temperature -6 degrees C., dewpoint -7 degrees C. A private pilot occupied the left seat, an ATP was in the right seat, and a student pilot occupied the rear passenger seat. There were no known details regarding a weather briefing or weather check prior to takeoff or in flight.
The next 3-fatal accident involved a Beech V35B aircraft on an instrument flight plan in IFR conditions, and on an ILS approach to Springfield, Illinois. The pilot reported a problem (unk), but continued the approach. The aircraft impacted terrain 3 miles out from the Outer Marker, on the localizer centerline. The weather at Springfield was reported as visibility 2.5 miles with mist, overcast at 500' agl, temperature 3 degrees C., and dewpoint 2 degrees C. The next fatal accident, (2 fatal) involved a Beech 200 aircraft, a corporate - Executive flight, impacting a hangar at Salmon, Idaho, after takeoff in a snowstorm, trying to maintain VFR flight prior to clearance delivery of an IFR clearance by ARTCC. The weather conditions were not reported (obviously IFR conditions).
Another 2-fatal accident involving an instrument-rated pilot in a Cessna 210N on a X-C IFR flight plan collided with ground at Bloomsfield, Kentucky. The last known communication with ATC indicated that the pilot "read back" a clearance to descend from 8,000' to 6,000'. Radio and radar contact with the flight was lost. The weather was not reported. The next 2-fatal accident involved a Cessna R182 Commercial Flight Instructor and a student on a night, no flight plan, instructional flight from Orlando, Florida to Meridianville, Alabama. No weather was reported. The aircraft crashed near Woodland, Alabama.
There were two 1-fatal accidents involving collision with ground while maneuvering in night VFR conditions; one a Piper PA-28 near Ortiz, Washington, circumstances unknown, and a PA-32 on a night marginal VFR X-C flight near Warren, Wiisconsin. The weather near the accident site was visibility 6 miles, haze, overcast at 1,800 ', temperarture 2 degrees C. and dewpoint -2 degrees C. A witness near the accident site reported ground fog. Another 1-fatal Piper PA-28 involved a night forced landing when the engine quit near Augusta, Georgia; and a 1-fatal Beech 60 aircraft impacted terrain on a VFR X-C takeoff at Newcastle, Delaware. The weather was reported as wind 21 knots, gusting to 26 knots, visibility 10 miles, temperature 0 degrees C., and dewpoint -3 degrees C. At the accident site the gear was found retracted, the right flap was fully extended, and the left flap was fully retracted. Both flaps were observed extended prior to takeoff.
There were 4 Homebuilt aircraft accidents and 1 Sports aircraft accident, and 1 gyrocopter accident reported. One Homebuilt accident, killing the pilot, impacted trees on takeoff when the canopy opened and a fabric cover exited the cockpit and contacted the propellors. Two other serious injury accidents; one stalled on takeoff, and the other lost engine power inflight. Another Homebuilt, a Vans GA, lost complete power in flight and nosed over on landing. The pilot visually verified that both fuel tanks were full prior to departure (providing a range of 3 hours and 45 minutes of flight). At the accident site, both fuel tanks were found to be empty. The 2-fatal gyrocopter accident, an Althouse RAF 2000 GTX, contacted ground near Cromley, Texas, apparently an engine problem. A Sport pilot in a Garniss STOL 701 was killed during an apparent buzzing accident.
Four other accidents were reported, one a Mooney M20C when the engine caught fire inflight at night. The pilot managed a forced landing near Phillipsburg, Kansas. The pilot and a passenger received serious injury. Two ATp's in a Cessna 551, with 6 passengers, landed at Coeur d' Alene, Idaho in 21/2 inches of snow slush, and departed the runway when the nosegear failed. The pilot was told there was 3/4 inch of snow on the runway. Another, a Piper PA-30, sustained substantial damage when the landing gear collapsed during the landing roll at Bridger, Montana. And a Cessna 152 was damaged during a forced landing following loss of engine power during cruise near Ft. Worth, Texas. The student pilot was not injured.
The majority of the fatal accidents were weather-related. We'll wait out the NTSB Investigator's findings on those accidents.
A word or two regarding the GA and fatal accident rates for 2007. Some of the aviation experts have stated or indicated a reduction in those rates for 2007 from 2006. The data, however, based on the best available, does not really indicate a reduction. Rather, a slight increase in the GA rate and a slight decrease in the fatal accident rate. Based on accidents / 100,000 flying hours, the reported rate for 2006 was 6.64 and 1.32. The computed rates for 2007, based on NTSB accidents through November 2007 and the addition of the December accidents result in rates of 6.78 and 1.24 respectively. And a higher number of
accident and fatal accidents in December would increase the rates, and a lesser number of flying hours (from the estimated) would also increase the rates.
Thanks for listening. R.S.

Aviation Weather Services

Hi Readers: Aviation Weather Services promolgated by the FAA, the NWS, and NASA are best described by and necessarily involve the actual flight, local or x-c, VFR and IFR flight plans; beginning with flight planning, and leading to en route flight, and terminating with descent and approach to land. In addition, the Weather Services provide an assist to the Controllers in preparing for the duties in which they are charged. Even local flights must be considered in terms of current weather - often pilots on local flights are caught in a sudden change of weather from VFR to IFR, as many of the aircraft accidents reveal.
Weather is a 24-hour phenomenom, in constant change of its elements and phases. In 20 minutes a cloud ceiling may ascend or descend 2,000 feet, precipitation can change from rain to ice, and visibilities can become obscured or obliterated.
Since most weather services are tied to a specific phase of flight, let's plan a VFR x-c flight. Without getting into the details, we would either file a flightplan with AFSS/FSS by telephone using TIBS (Telephone Information Briefing Service), a recording of the destination current weather, or talking with a weather specialist concerning the destination current and forecasted weather (1-800-WxBrief- toll free). This is a Preflight Briefing to help the pilot determine a "go" or "no go" decision. Or, if you are computer-oriented, you may file a flight plan with DUATS(Direct User Access Terminal System) - toll free, and get alpha-numeric preflight weather data and file a domestic VFR or IFR flight plan.
We might use, in conjunction with our flight plan or separately, METAR (Aviation routine weather report) or an FA(an area forecast), if advantageous.
After takeoff, we are considered in an en route phase of flight and can utilize several services to our advantage.
Lest we forget, we can still communicate with AFSS/FSS on a common frquency of 122.2 or a discrete frequency for an individual station to file, activate, close, or change a flight plan; request an IFR clearance, contact ATCT/ARTCC for control; file position reports, pass PIREPS (Pilot weather reports); request status of Special Use Airspace; and request assistance in an inflight emergency.
Normally, we might use EFAS (En Route Flight Advisory Service) for nonroutine weather needs in flight or TWEB ( Transcribed Weather Broadcasts) for the routine weather needs in flight. Inflight advisories include SIGMET (Significant Meteorological Information), Convective SIGMETs, AIRMETs (Airmen Meteorological Information), FAs (Area Forecasts) , Winds Aloft Forecasts (176 locations in 48 States), and PIREPs (Reports by pilots of weather conditions in flight).
Descending from en route flight to approach and landing at our destination we might use any number of weather advisories, primarily that concerning the weather at the destination airport or terminal such as FA, LLWAS (Low level wind shear alert system), PIREPs, TAF(Terminal Area Forecast), and WW (Severe Weather Watch). And, of course, our continued communications, depending on VFR or IFR, with ARTCC, TRACON ( Terminal Radar Approach Control), ATCT, and following with GT (Ground Control) to the very end of our flight.
ATCT and TRACON both use air/ground communications, visual signals, and other devices to provide ATC services to aircraft operating in the vicinity of an airport. ATC services authorizes aircraft to land or takeoff at the airport controlled by the tower or to transit the Class D airspace area regardless of flight plan or weather conditions. A tower may also provide approach control services.
To put the aviation weather services in perspective, the pilot must deal with ARTCC, ATCT, and TRACON (as spelled out in AC 00-45F) with respect to their flight plan to effect location and positive control of the aircraft. TRACONs manage the airspace 10 to 400 miles outside of selected airports and below 13,000 feet. They also coordinate spacing as aircraft approach and depart airports. Terminal Controllers are knowlegeable of current weather conditions and are prepared to advise pilots of hazardous weather conditions within a 150 nm sector or area. Tower operators are certified to act as official weather observers.
The December 2007 aircraft Accident Accounting is in process.
Thanks for listening. R.S.

October 2007 aircraft Accident/Incidents

Hi Readers: It time to review the October Accidents/Incidents as reported by NTSB ( There were none reported for Oct 1, 30th, and 31st).
Therewere 74 accidents (4 incidents)( 3 non-U.S. accidents) of which 23 were fatal accidents accounting for 48 fatalities. One fatal accident occurred in Venezuela, accounting for 2 fatalities; one fatal accident occurred in Switzerland, accounting for 2 fatalities; and one Beech D55 accident (1 fatality) occurred near St.Croix, Virgin Islands - apparenty encountering IFR weather. Twenty fatal accidents occurred in the Continental U.S. accounting for 43 fatalities.

There were 4 Incidents during October - one, an Airbus 320 landing at Fargo, North Dakota with the nosegear turned 90 degrees, incurring minor damage; another, an Airbus received minor damage after landing when it struck a runway light at Chicago O'Hare Intl airport. In another incident, classified as a pilot deviation, a Cessna 525 made takeoff from Taxiway M, rather than Runway 36L, at Memphis Intl airport against Controller instructions. In the 4th incident a Bell Helicopter made a forced landing in the Gulf of Mexico.

There were 4 balloon landing accidents at Albuquerque, New Mexico - all during the International Balloon Fiesta, and all striking objects on landing (due to wind and gusts) resulting in one fatality, 7 serious injury, and one minor injury.

There was one amateur-built gyroplane accident (one fatal, one serious injury) due to engine failure and resulting in impact with trees. One glider crashed during day VFR maneuvering (one fatal). A formation flight of Yakovlev Yak50 aircraft landing atGillespie Field, El Cajon, CA. resulted in a collision of 2 aircraft on the landing runway; and a Piper PA-32R collided with a Cessna 152 in the traffic pattern at Farmingdale, New York - there were no injuries.

The remaining fatal accidents were a conglomeration of day and night flights - an interesting study of accident causes and safety aspects: To begin, there was a 10-fatal Cessna 208B Caravan propjet on a 402 mile VFR night flight (returning 9 skydivers from a skydiving event near Boise, Idaho to a home base in Shelton, Wa.) that crashed about 45 miles WSW of Yakima, WA. at about 4,300 ft. msl, just south of Mt. Ranier, in IFR weather. There were indications of a rapid descent (6,800 ft/min) from 8,900 ft. and a power-on impact with mountainous terrain at 4,300 ft. msl. Low clouds, misty rain, and low visibility were reported in the area of the accident site, and a hunter in the area observed the aircraft first on horizontal flight, followed by vertical flight. Icing and loss of control were indicated.
The FAA reported that no service was provided to the pilot, there was no flight plan, and there was no record of a preflight or other weather briefing. The report noted VFR weather conditions generally along the route of flight, but IFR conditions in the Cascade mountains and western foothills. There was an AIRMET for icing, low-level turbulence, and mountain obscuration. (I can't imagine a Commercial pilot based at Shelton, Wa. not being clued-in on the weather, in that area, particularly in October). This particular airplane was equipped with analog gauges and digital avionics, including autopilot, GPS, transponder, and de-icing boots. The Mode C transponder was operating and FAA radar was tracking the airplane and observed the target, first at 14,400 ft, then at 13,000 ft, and then 8,900 ft, all in a matter of seconds. The NTSB and Cessna Aircraft are investigating the accident. In armchair analysis (based on what has been reported), I would have to say, in spite of the analog and digital instrumentation of the airplane, that this pilot demonstrated how not to conduct a VFR night x-c flight.

A second accident (5 fatal) involved a Beech A36 forced landing on takeoff and impact with power lines during variable direction and velocity of high winds and gusts. The aircraft was unable to gain altitude and maintain climb speed. Witnesses reported a rough engine. The pilot was IFR qualified and an IFR flight plan had been filed. Visual flight conditions existed. I wonder if this airplane was overloaded.

The remaining fatal accidents (11) involved an Aero Commander 560F (4 fatal) that impacted terrain after takeoff with a possible engine failure; a Rathyeon C90A (3 fatal) on a night VFR Medical flight which crashed during en route descent; a Cessna 310N (2 fatal) at 13,000 ft in icing conditions with an engine problem; a Cessna 150L (2 fatal), an Instructor and student, impacted terrain during takeoff climb - loss of power and loss of control indicated; a Piper PA-28 (2 fatal) on a night VFR x-c flight encountered IFR conditions and impacted trees and the ground; a Piper PA-28 impacted terrain on a night flight to Las Vegas - encountering IFR conditions; a Piper PA-18 collided with powerlines on a day VFR flight; A Bellanca 7GCBC aircraft crashed on a day VFR x-c flight - an outer wing failure indicated; and another Bellanca 7GCAA crashed due to loss of control following a tailwheel shimmy during a glider-tow operation; an Amateur-built Lambert Variez aircraft crashed during the pilot's test of an installed speed brake; and a Piper PA-18 collided with power lines on a VFR flight.

The October accidents indicate loss of control associated with aircraft and weather factors, along with doubtful flight planning and en route weather knowledge and awareness. Icing conditions, which can appear at any time of the year, seem to be a particular problem to pilots. Knowing the freezing level in weather and how to avoid the icing conditions is of the utmost importance. Pilots should learn how to use all the available weather, and weather-forecasting services, prior to and during en route flight. And, in spite of advanced instrumentation and the services available, pilots will always have to make the decision to fly or stay, or to choose an alternate, or land at the first available airport - and it may not be easy.
Thanks for listening. R.S.

Ceiling and Visibility

Ceiling and visibility are two basic weather elements which must be considered in all flying beginning with your flight planning. Normally we don't give the two elements much thought. We look at the sky - it's either cllear or cloudy. And we look out and around to see how far we can see objects. But for flying, the broad perspective must be narrowed to specific judgments.
The FAA's definition of ceiling is "the height above the earth's surface of the lowest layer of clouds or obscuring phenomena that is reported as broken, overcast, obscuration, and not classified as thin or partial". Pretty wordy and a little confusing, yes?
Well, let's get practical - if you cannot see clouds in the sky or you have something like fog or haze, you have either no ceiling at all or you have ceiling zero, depending on whether the condition is thin or heavy in obscuration.
Weather Observers classify clouds 3/10 or less as scattered, 6/10 as cloudy or a ceiling, 10/10 as overcast. And, of course, heavy fog would be obscuration or ceiling zero.
Now visibility is another matter. We usually think of seeing objects in terms of miles (statute), say 1/4 mile, 1/2 mile, 1/ mile, 3 miles, etc., a matter of distance judgment - relating much to visual acuity used in connection with takeoff, landing, and clearances, and VFR and IFR flight. In fact, ceiling and visibility appears as the first pair of elements used in our flight planning.
As stated (all too simply) in the FARs (Federal Air Regulations), IFR flight is weather conditions below the minimums for flight under VFR conditions.
In any case, to the pilot ceiling means dealing with clouds, sky cover, at what altitudes, and their movement over time. Visibility relates to all kinds of weather conditions - rain, snow, fog, smoke, and haze in connection with all phases of flight and appears perhaps as the first defining factor in planning whether you fly VFR or IFR.

Use the checklist !!

USE THE CHECKLIST!

What checklists? Granted there are checklists all over the place in aviation - flight preparation, pre-flight, flight planning, inflight planning, etc.
Right now we are talking to the pilot about flying the airplane.
The manufacturer of the airplane provides the Operating Manual - perhaps called the Flight or Pilot manual- which must be carried in the airplane, along with the Airworthiness Certificate, and other documents, aircraft and Engine logbooks, Squack Sheets, et. There are reasons for these documents to be carried in the airplane: 1. The Operating manual gives us each step of the procedues for operating the airplane, including coping with emergencies, 2. The other documents relate to the airworthiness and the flyable condition of the airplane and its engine. In effect the Operating manual is the checklist, beginning with the Walkaround inspection, engine start, pre-takeoff duties, and operation of each phase of flight (takeoff, climb, cruise, descent, pre-landing and landing -followed by engine shutdown).
Why the checklist? Since we are human beings and subject to human error - mistakes - and at times are forgetful, particularly during excitement and stress. We like excitement; stress we do not want. Stress is an assidious condition that appears automatically when we exhibit uncertain action, untimely acts, and sometimes stupid mistakes. I hate to mention the number of aircraft accidents over the years caused by the pilot's failure to extend the gear prior to landing - gear extention, the most important item on the prelanding checklist.
But let's not think of accidents - rather safe flying.
FAA Part 91 General Operating Flight Rules cover the Private Pilot certificate and VFR (Visual Flight Rules)
Flying, including airplane airworthiness standards, airplane flight manual rquirements, VFR fuel requirements, VFR flight plans, and basic weather minimums - all relating to checklists of one type or another. Let's conclude that the airplane manufacturer has complied with Part 91 in providing the Operating manual for the airplane we are going to fly. It's our best checklist - in the left seat of the airplane. Let's get started. RS.