Glider Pilot Aeronautical Knowledge Review

by Mr. Frank S. Phillips, Jr.(Webmaster 注:出典”FAA AVIATION NEWS MARCH 2002″ よく整理されているので参考に)

It’s a beautiful day! Let’s go soaring!
How many times have you heard or said these words?
Before you go, here’s a refresher list of things you should remember from your student pilots days. It’s also a good reminder of the many facts needed to pass the glider practical test.
Remember, for any flight, determine RUNWAY(s) length, get all available information, and use checklists!


  • Briefing

1-800-WXBRIEF : give “N” number, type of aircraft, location, planned route (if cross-country), time of flight, etc. Ask for NOTAMs (distant and local).



Issued for moderate icing and turbulence, winds 30 KTS +, visibility less than 3 miles, ceilings below 1,000′.


Issued for all aircraft for severe/extreme turbulence, icing, obstructions to visibility.

  • Convective SIGMET

Issued for tornadoes, lines of thunderstorms; embeded thunderstorms; hail 3/4 inch +.

  • Ceilings

Lowest reported broken, obstruction, or overcast cloud layer (height AGL).


Clouds with the greatest turbulence. (AVOID by 20 NM)

Dewpoint Cloud Base

Temperature at which visible moisture forms when the air saturates.

Temperature and dewpoint in upward moving air converge at rate of about 4.4F or 2.5C/1,000 feet (to estimate cloud base, devide Fahrenheit ground spread by 4 [Celsius, by 2.2] and multiply result by 1,000 feet.

  • Vision Obstructions

Are fog, haze (worse when flying into the sun), rain, smoke, smog

  • Front

Warm Front

Temperature inversions (goes up with altitude); poor visibility; smooth/stable air; stratiform clouds; drizzle; fog (forms from evaporation of precipitation).

Cold Front

Temperature goes down with altitude; good visibility; turbulence/unstable air; cumuliform clouds.

  • Soaring Forecast : Thermal Index (TI)

Thermals depend on sinking cold air that forces warm air upward.

The strength of thermals (TI) is shown by difference between the dry adiabatic laps rate (5.4F/3C per 1,000 feet from the forecast maximum or trigger temperature) and the actual laps rate. The greater the negative difference at a given altitude, the stronger the lift will be at that altitude.

  • Thunderstorms (TS)

Lifting, moisture, unstable air, and lightning (always);

developing/cumulus stage = Updrafts;
mature stage = rain;
dissipating = down drafts.


  • Squall Line TS

Narrow band of thunderstorms and are most intense hazard to aircraft.

  • Winds

Reported aloft true direction, in knots; on the groung, reported as magnetic.


  • I’M SAFE?


  • Self-Certification

Know of or reason to know of any condition that affects ability to fly safely.

  • Alcohol

Do not fly within 8 hours of use; under the influence; or with more than 0.04% BAC.

  • To Act as PIC

Must have pilot certificate and had a flight review within 24 calender month.
(WINGS Progrum may substitute for flight review.)

  • To Carry Passengers

3 takeoffs and 3 landings as sole manipulatorof glider in preceding 90 days.



Airworthness Certificate
Registration Certificate
Radio License (for international flights)
Operating limitations
Weight and balance information or data

  • Airworthiness

Owner/operator maintains, but PIC responsible to determine airworthiness.

  • Assembly

A pilot certificate holder may assemble or disassemble a glider if specified in the glider flight manual.
Pilot must make a maintenance record entry of the work performed description, pilot’s name, and date.

  • Control Chack

ALWAYS! Perform POSITIVE CONTROL CHECK after each assembly!
ALWAYS! Perform a POSITIVE CONTROL CHECK before each flight!

  • Inspections

Must have annual inspection and comply with AD’s.
A 100 hour, if for hire.

  • Towline Strength

Towline; not less than 80% nor more than 200% the gross weight of glider.
If towline strength more than twice, install safety (weak) links; one at glider, 80% to twice gross weight; and one at tow plane , greater in strength than one at glider, but not more than 25% greater or twice glider weight.

  • Oxygen System

PRICE check;







  • Weight and Balance


= basic empty weight (including optional equipment)

+ occupants and gear.

  • Center of Gravity (CG)


Worse stability, lower stall speed, better performance.


Better stability, higher stall speed, worse performance.

  • Ballast (check)

If needed, install properly! Use to adjust CG or to meet CG limits.
Ballast (often water) may be used to alter the best L/D speed (see below).

  • Density Altitude (DA)

Determines performance.
As DA increases, performance will decrease.
DA increases as temperatures increase;
DA increases as pressure lowers.

  • Pressure Altitude (PA)

Set altimeter to 29.92″ (or calculate: 1″Hg = approx. 1,000 feet of altitude)

  • L/D (Lift/Drag) Ratio

When Lift over Drag ratio is greatest (maximum lift, minimum drag), best glide is achieved (most horizontal distance for each foot of altitude lost). Best L/D speed varies with weight. As weight increases, best L/D speed increases. (L/D is a function of wing design and is constant, regardless of weight.)

  • Minimum Sink Speed

Speed at which least loss of altitude occurs in a given period of time. As weight increases, minimum sinkspeed (sink rate) increases.

  • Rules of Thumb : “SPEED TO FLY”

Speed up in sink (between thermals).
Slow down in lift (minimum sink speed for bank).

With sufficient altitude, when using variometer speed ring, fly down rate = to average rate of climb in last thermal, or with less sophisticated instruments,
> In good conditions, fly approximately 20% above best L/D.
> In poor conditions, fly the best L/D.

  • Cross-country Profile

Used to determine minimmum enroute altitude at any particular point in flight.
> Safety margin : plan using 1/2 of published L/D for loss of expected lift
> Glide ratio varies with wind (head wind decreases it; tail wind increases)
> For a tail wind component, plan to fly using the best L/D airspeed.
> For a head wind component, plan to fly L/D plus 1/2 estimaitd head wind.
> Plan to leave departure airport and arrive destination airport at 1,000′ AGL.
> Plot minimum altitude lines for glide to departure and destination airport.
> Lines will show go-ahead minimum altitudes for flight


  • Angle of Attack (AOA)

Angle between relative wind and chord.
Increasing AOA, increases lift and drag.
[Note: If weight or wing loading is increased, more lift will be required].

  • Stalls

Occure at a specific AOA.
A stall can occur at any airspeed or any atitude.
Stall speed increases with weight (higher angle of attack to get more lift).
Turns increase stall speed due to higher load factor.

  • Spins

A glider must be stalled to spin (a spin is an aggravated stall).

  • Three Forces in Flight

Lift, drag (induced and parasite),
and gravity (glider weight acting downward).
Total drag = induced (decreases with speed) + parasite (increases with speed)


  • Local Procedures

Be familiar with local field conditions and signals (may vary from site to site)

  • Pre-flight Briefings

Pre-flight discussion with tow pilot on all procedures, including emergencies

  • Plan of Action

Before each launch, have a plan of action (situational awareness)

  • Passengers

On how to exit; on seat belt use, and notify to fasten before takeoff/landing

  • Parachutes

If used, review procedures for use and brief passengers on proper use

  • Airspeed Indicator

White arc shows flap range
Green arc shows normal range
Yellow arc shows caution
Red line shows never exceed speed

  • Magnetic Compass


Overshoot South, Undershoot North.
= Lags North of East and West headings, and leads South of East and West


On East or West heading, Accelerate, it turns North; Decelerate, South.

  • Take-off Roll

At lift off avoid excessive back pressure, wait for tow plane to lift off and climb

  • Towline Break :

FLY GLIDER 1ST, then evaluate situation: wind, obstacles, altitude, etc,;
> If safe landing can be made ahead, land ahead, into the wind.
> If sufficient altitude has been attained to return safely to field (usually at least
200 feet = 180 deg. turn (reverse course)
400 feet = 270 deg. turn (reverse base and final)
or more above the field elevation), return to field.

  • Airborne Signals

Turns (Prohibited at Seminolelake G.P.)

Left, glider moves to right and gently pulls tow plane tail.
Right, left, then same.

Speed change

> Faster, glider rocks wings directly behind tow plane.
> Slower, glider fish tails directly behind tow plane.

Spoilers Out

Tow plane waggles rudder (not a yawing motion).


> If glider cannot release, maneuver to a tow position visible to tow pilot and rock wings. After assuring tow pilot understands, maneuver back to normal tow position that will avoid tow rope coming back over wing.
> If tow pilot unable to release , tow pilot signals with yawing motion.

Severe Turbulence

Maintain level flight attitude and use V a (maneuvering speed) or lower speed.
Note : Va (not shown on airspeed indicator) varies with weight
as weight goes down, Va goes down.


  • Class A

18,000′ MSL to FL600, set altimeter to 29.92″; requires IFR or ATC authorization.

Air Traffic Control facility having jurisdiction for the specific Class A airspace.

  • Class B

(Blue line)
must have ATC clearance and Mode C transponder to enter.

  • Class C

(Magenta line)
must establish 2-way communication with ATC & Mode C transponder.

  • Class D

(Dashed blue line)
has operating control tower; must establish communications.

  • Class E

Blue tinted line indicates a floor 1,200′ AGL or greater that abuts Class G airspace.
Magenta tinted line indicates a floor at 700′ AGL.
Dashed magenta line indicates Class E starts at surface (surface area Class E).
Broken blue line (off set, jagged line) indicates floor of Class E greater than 700′ AGL.
(See aeronautical chart)

  • Class G

is any airspace other than controlled airspace (outside of Class A,B,C,D and E).

  • Class E or G

Operating control tower shown as blue airport; communication 4 NM, 2,500′ AGL.

  • MOA

(Magenta colored line with magenta hash marks)
military operations, use caution.

  • Restricted Area

(blue “R”, blue line with blue hash marks)
enter only with controlling agency okey,

  • Prohibited Area

(blue “R”, blue line with blue hash marks)
do not enter; it’s a “NO, NO” to be there!

  • Gray line :

Military training route with speeds greater than 250 knots;
VR indicates VFR; IR, IFR
4 digits indicates flights at and below 1,500′ AGL; 3 digits, from surface up.

  • Federal Airway

4 nautical miles either side of blue line (Vector airway), from 1,200′ AGL to FL180.

  • Traffic pattern

Traffic pattern indicates depicts the direction that airplanes turn in pattern.

  • VASI

“All red, you’re dead (LOW); red over white, you’re all right.” (All white, too high)

  • Transponder

7700 – Emergency use
7600 – No radio
7500 – Hijack
1200 or as ATC assigns – VFR
As assigned by ATC facility – IFR (glider pilot must have instrument airplane rating)

Mode C:

Over 10,000 MSL, B and C airspace; above C; and Mode C veil (30 NM of Class B)

  • Oxygen

Crew 12,500 – 14,000′ MSL over 30 minutes; crew above 14,000′ MSL; all over 15,000′ MSL.

  • ELT

Test during first 5 minutes after hour; replace battery after 1 hour cumulative; change at 50%.

  • Emergencies

Pilot may deviate from any rule to meet an emergency and if requested and get handling priority, must submit detailed report within 48 hours if requested by ATC manager.
Declare emergencies to ATC, or if not taking to ATC, use 121.5 MHz or 243 MHz.

  • EFAS

For enroute weather advisories (above 5,000′ AGL) contact: FSS122.0 MHz.

  • Right of Way

Aircraft (A/C) in distress have right of way (ROW) over all other A/C;
balloons over other A/C;
gliders over airplanes, rotorcrafts, and airships;
A/C towing or refueling over other powered A/C.
When head-on, go to right.
Overtake other A/C, pass to the right (note ridge below).
Landing A/C has ROW.
LOwer A/C on final has ROW.

  • Ridge Flying

The industry guidelines for ridge soaring (check for local conditions that vary):
approach ridge at shallow angle;
never pass directry over or under other gliders flying the ridge;
pass slower gliders on inside toward the ridge ;
make all turns away from the ridge into the wind;
if approaching each other head on, give way to the right.

  • Thermals

Fly at minimum sink speed, make turns in same direction as other gliders.

  • No Aerobatics

No intentional abrupt maneuver unnecessary for normal flight over congested area or open air assembly; on Federal Airway, below 1,500′ AGL; or less than 3 miles visibility.

  • Light Signals (from control tower)


Flashing Green – TAXI
Red – STOP
Flashing Red – CLEAR RUNWAY
Red/Green – CAUTION


Green – LAND
Red/Green – CAUTION

  • Minumum Altitude

Sparse Areas
500′ AGL. No hazard to and 500′ from persons/property.
Congested Areas
1,000′ above highest obstacle within 2,000′ radius.

  • Altimeter Settings

Use reported barometic pressure.
If none available, use field elevation.
Over 18,000′ MSL (must have ATC authorization), set altimeter to 29.92″.


  • Parachutes

Unless each occupants is wearing an approved parashute, a pilot carring any person other than a crew member, may not execute any intentional maneuver more than 60 deg. bank, 30 deg. pitch up/down.
Always brief on use and proper fit!


If available for emergency use, must be packed by certificate and appropriately rated rigger within preceding 120 days if a chair type, or if other type:
Nylon, rayon, or similar synthetic material within preceding 120days
Silk, pongee, or other natural fiber within preceding 60 days

  • Survival Gear

Food, water, clothing, and equipment appropriate to planned flight environment.

  • Landing Out

Be prepared for unplanned landings at all times, especially on cross-country flights.

Industry standards recommend to start serious search at 3,000′ AGL; at 2,000′ AGL, narrow options to select a specific, safe field by 1,500′ AGL


  • Dehydration

Water depletion: carry and drink water to replenish bodily fluids.

  • Fatigue

Causes below par performance; get proper rest and stop flying when tired.

  • Heat

Aggravates dehydration and fatigue

Dehydration, heat, and fatigue can impact judgement and performance

  • Hypoxia

Oxygen deficiency.
Go lower or use oxygen.
Smoking/night increase effect.

  • Hyperventilation

Caused by rapid breathing, often from stress;
hold breathe or breathe into bag.

  • Scanning

Scan in segments of 10 deg. for at least one second to allow eyes to focus.

  • Spatial Disorientation

Temporary confusion, rely on instrument indications, not body signals.


Avoid Large Aircraft Tip Vortices.
Avoid Flight Below, Behind, and Downwind of It’s Flight Path.



Must report immidiately an in-flight fire, an overdue aircraft, a flight control system mulfunction of failure, incapacity of crewmember to perform duty due to injuly or sickness, damage to property (other than aircraft) exceeding $25,000 (estimated).


Must submit report within 10 days.


Report on request.

Have a safe soaring flight !!

(Statute mile [sm] visibility and cloud clearance)
= Coming Soon…