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FAA commercial glider pilot theory foundations study materials
FAA commercial glider pilot theory foundations study resources

FAA commercial glider pilot theory foundations practice questions

One question at a time. Build your FAA commercial glider pilot theory foundations understanding.

First 50 of 190 questions. Each one lists the choices, the correct answer, and an explanation. The checker at the top of this page saves progress in this browser when it is available.

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Question 1Decisions, human factors and FAA scope

Does a person exercising commercial glider pilot privileges need an FAA medical certificate?

  1. Yes, at least a second-class medical certificate
  2. Yes, a third-class medical certificate
  3. No medical certificate is required for glider operations Correct answer.
  4. Only BasicMed is required

Explanation

14 CFR 61.23 specifies that a medical certificate is not required to operate a glider or balloon. The pilot must still not have a known medical deficiency that would make them unable to operate safely.

Question 2Decisions, human factors and FAA scope

Which 14 CFR part contains the general operating and flight rules that apply to glider operations, including right-of-way and towing?

  1. 14 CFR Part 91 Correct answer.
  2. 14 CFR Part 61
  3. 14 CFR Part 121
  4. 14 CFR Part 135

Explanation

14 CFR Part 91 contains general operating and flight rules, including right-of-way rules and 91.309 towing requirements, that apply to gliders. Part 61 covers certification of pilots, not the operating rules.

Question 3Decisions, human factors and FAA scope

Under right-of-way rules in 14 CFR 91.113, when a glider and an airplane are converging at approximately the same altitude (and neither is in distress), which generally has the right of way?

  1. The airplane, because it is faster
  2. The glider Correct answer.
  3. The aircraft on the left
  4. Whichever is higher

Explanation

14 CFR 91.113 establishes a right-of-way hierarchy in which a glider has the right of way over an airplane (less maneuverable categories such as balloons rank highest, then gliders, then airplanes). The more maneuverable aircraft must give way.

Question 4Decisions, human factors and FAA scope

Before each aerotow takeoff, the glider pilot and tow pilot should:

  1. Skip briefing if they have flown together before
  2. Only check the weather
  3. Conduct a takeoff and emergency briefing, including signals and decision altitudes for rope breaks Correct answer.
  4. Rely on radio calls during the climb

Explanation

A pre-takeoff briefing covering signals, abort criteria, and rope-break decision altitudes (low, mid, and pattern-altitude actions) is essential because emergencies happen fast and there is no time to negotiate procedures during the launch.

Question 5Decisions, human factors and FAA scope

Hypoxia becomes a significant concern for glider pilots primarily because:

  1. Gliders are pressurized and leaks are common
  2. Gliders generate carbon monoxide from an engine
  3. Hypoxia only occurs below 5,000 feet
  4. Wave soaring can take a glider to very high altitudes where supplemental oxygen is required Correct answer.

Explanation

Mountain wave can carry gliders to very high altitudes where the partial pressure of oxygen is too low; supplemental oxygen is required per 14 CFR 91.211 above the specified cabin altitudes to prevent hypoxia. Recognizing early symptoms is critical.

Question 6Decisions, human factors and FAA scope

What is the main risk-management reason to set a personal minimum 'decision altitude' to stop searching for lift and commit to a landing?

  1. To increase the glide ratio
  2. To ensure a safe, unhurried pattern and landing rather than a low, rushed, stall-prone approach Correct answer.
  3. To raise the MacCready setting
  4. To reduce wing loading

Explanation

Committing to land at a predetermined altitude prevents the common trap of stretching a search for lift too low, which leads to rushed patterns and stall/spin accidents; a disciplined decision altitude preserves time and energy for a safe approach. This is a core aeronautical decision making practice.

Question 7Decisions, human factors and FAA scope

When carrying a passenger for a commercial sightseeing flight, the pilot's pre-flight safety briefing to the passenger should at minimum include:

  1. Only the destination
  2. Seatbelt/harness use, canopy operation, emergency egress, and not interfering with controls Correct answer.
  3. The glider's purchase price
  4. The pilot's logbook totals

Explanation

A passenger safety briefing should cover harness use, canopy and emergency egress, parachute use if provided, and instructions not to touch the controls; this is both good practice and consistent with the pilot's safety responsibilities.

Question 8Decisions, human factors and FAA scope

Spatial disorientation risk for a glider pilot increases most when:

  1. Flying straight and level in clear air with a visible horizon
  2. Reading the variometer on the ground
  3. Circling for long periods in or near clouds or in poor visual reference conditions Correct answer.
  4. Performing a normal aerotow in clear conditions

Explanation

Prolonged turning with a poor outside reference, such as near cloud base or in haze, can produce vestibular illusions and spatial disorientation; gliders are generally not equipped or authorized for sustained IMC, so maintaining visual reference is critical.

Question 9Decisions, human factors and FAA scope

What is the chief reason a commercial glider pilot briefs and uses a consistent traffic pattern and pattern entry at the home gliderport?

  1. Patterns are optional for gliders
  2. Gliders can always go around
  3. To increase glide ratio
  4. Predictable pattern flow improves separation from other gliders/tow operations and supports a safe, energy-managed approach with one chance to land Correct answer.

Explanation

Because a glider normally has one opportunity to land (no go-around), a consistent, briefed pattern improves traffic predictability and ensures the pilot arrives with appropriate energy and spacing for a safe approach and touchdown.

Question 10Decisions, human factors and FAA scope

Which best describes proper risk management when the day's conditions are weaker and lower than forecast during a cross-country flight?

  1. Reassess continuously, adjust speed-to-fly down, keep landable fields in range, and be willing to shorten the task or land out safely Correct answer.
  2. Continue the original task regardless of conditions
  3. Increase the MacCready setting and push on faster
  4. Ignore the changing conditions until low

Explanation

Sound aeronautical decision making means continually reassessing, lowering the MacCready/speed-to-fly as lift weakens, protecting reachable fields, and accepting a shortened task or a safe planned landout rather than stretching the glide dangerously.

Question 11Decisions, human factors and FAA scope

A commercial glider pilot is asked to give a paid ride but is fatigued and conditions are marginal. The best aeronautical decision is to:

  1. Always fly because the customer paid
  2. Fly faster to finish sooner
  3. Let the passenger decide
  4. Apply personal minimums and a risk assessment (such as a fatigue/IMSAFE and conditions check) and decline or delay the flight if the risk is unacceptable Correct answer.

Explanation

Commercial pressure does not override safety; using personal minimums and a structured risk assessment (for example IMSAFE for fitness and a conditions/PAVE review) and being willing to delay or cancel is the correct aeronautical decision-making response.

Question 12Soaring aerodynamics, polar and loading

On a glider polar curve, the airspeed that produces the minimum sink rate is best used for which objective?

  1. Maximizing distance over the ground in still air
  2. Penetrating into a strong headwind
  3. Achieving the steepest descent for landing
  4. Staying aloft the longest while thermalling or in lift Correct answer.

Explanation

Minimum sink speed is the tangent point at the top of the polar where vertical descent rate is lowest, so it maximizes time aloft, which is ideal when working weak lift or thermalling. It is slower than best L/D speed.

Question 13Soaring aerodynamics, polar and loading

According to MacCready speed-to-fly theory, how should a glider pilot adjust cruise speed when expecting strong lift in the next thermal?

  1. Fly faster between thermals Correct answer.
  2. Fly slower to conserve altitude
  3. Maintain best L/D speed regardless of expected lift
  4. Fly at minimum sink speed at all times

Explanation

MacCready theory says the optimum inter-thermal cruise speed increases as the expected climb rate in the next thermal increases. Strong anticipated lift justifies flying faster because lost altitude is quickly regained.

Question 14Soaring aerodynamics, polar and loading

What is the primary aerodynamic benefit of carrying water ballast in a high-performance glider on a strong soaring day?

  1. It lowers the stall speed
  2. It increases the best L/D speed and improves inter-thermal cruise performance Correct answer.
  3. It increases the minimum sink rate advantage
  4. It reduces wing loading

Explanation

Water ballast raises wing loading, shifting the polar so the glider achieves its best glide ratio at a higher airspeed, improving cross-country speed when strong thermals offset the slightly higher sink in weak lift. Glide ratio itself is essentially unchanged.

Question 15Soaring aerodynamics, polar and loading

On the glider polar curve, the best lift-to-drag (L/D) airspeed is found at which graphical point?

  1. The lowest point on the curve
  2. The leftmost point on the curve
  3. The point where the curve crosses the zero-sink axis
  4. The point where a line from the origin is tangent to the polar Correct answer.

Explanation

Best L/D, which gives the maximum glide distance in still air, occurs where a straight line drawn from the origin is tangent to the polar curve, representing the flattest glide ratio. The tangent point at the top of the curve is minimum sink, a slower speed.

Question 16Soaring aerodynamics, polar and loading

When flying final glide into a strong headwind, how should the pilot adjust airspeed relative to the still-air best L/D speed?

  1. Fly faster than best L/D to reduce time exposed to the headwind and improve glide over the ground Correct answer.
  2. Fly slower than best L/D
  3. Fly exactly at best L/D regardless of wind
  4. Fly at minimum sink speed

Explanation

A headwind reduces ground distance covered per unit of altitude lost, so the optimum speed shifts to a faster value than the still-air best L/D to minimize time in the wind and maximize distance over the ground. Tailwinds shift the optimum slower.

Question 17Soaring aerodynamics, polar and loading

What is a forward slip primarily used for in a glider approach?

  1. To increase airspeed rapidly
  2. To lose altitude and increase descent rate without increasing airspeed, often when spoilers are insufficient Correct answer.
  3. To reduce drag for a longer glide
  4. To raise the nose during the flare

Explanation

A forward slip uses crossed controls to present the fuselage at an angle to the relative wind, greatly increasing drag and descent rate while keeping airspeed in check, useful to correct a high approach when spoilers alone are not enough.

Question 18Soaring aerodynamics, polar and loading

How does increasing wing loading (for example by adding water ballast) affect the glider's stall speed?

  1. It raises the stall speed Correct answer.
  2. It lowers the stall speed
  3. It has no effect on stall speed
  4. It eliminates the stall entirely

Explanation

Stall speed increases with the square root of wing loading, so adding water ballast raises the speed at which the wing stalls. Pilots must allow for higher approach and maneuvering speeds when ballasted.

Question 19Soaring aerodynamics, polar and loading

If a glider is loaded with the center of gravity (CG) aft of the approved limit, the most likely effect is:

  1. Increased longitudinal stability and a higher stall speed
  2. Reduced longitudinal stability and a greater tendency to enter and resist spin recovery Correct answer.
  3. No effect because gliders are inherently stable
  4. Improved stall warning margin

Explanation

An aft CG reduces longitudinal stability, making the glider more pitch-sensitive and increasing the tendency to enter spins while making recovery more difficult. Operating within the placarded CG envelope is required for safe handling.

Question 20Soaring aerodynamics, polar and loading

Before adding water ballast, the pilot must ensure the glider does not exceed which limitation?

  1. The minimum sink airspeed
  2. The maximum altitude
  3. Maximum gross weight and any maximum wing/water tank weight limits in the flight manual Correct answer.
  4. The radio frequency limit

Explanation

Water ballast must keep the glider within the maximum gross weight and any specific water-ballast or maximum-weight-of-non-lifting-parts limits in the flight manual and on placards. Exceeding structural weight limits is prohibited.

Question 21Soaring aerodynamics, polar and loading

What is the primary aerodynamic cause of a spin entry from a thermalling turn in a glider?

  1. Excess airspeed in the turn
  2. Spoilers left extended
  3. Carrying water ballast
  4. An uncoordinated stall in which one wing is more stalled than the other (yaw at the stall) Correct answer.

Explanation

A spin results from a stall combined with yaw, so one wing is more stalled and produces less lift than the other, causing autorotation; thermalling turns at low speed with adverse yaw are a classic setup. Coordinated flight and adequate speed prevent it.

Question 22Soaring aerodynamics, polar and loading

For maximum still-air glide distance with no wind and no usable lift expected, the MacCready ring/computer should be set to:

  1. A high value matching the strongest thermal of the day
  2. Zero, which corresponds to flying at best L/D speed Correct answer.
  3. The minimum sink value
  4. The stall speed

Explanation

A MacCready setting of zero corresponds to best L/D speed, giving maximum glide distance per altitude lost in still air when no further climb is expected, such as on a final glide with marginal altitude. Higher settings command faster cruise for better average speed when lift is available.

Question 23Soaring aerodynamics, polar and loading

Energy management in soaring refers primarily to the pilot's management of the trade-off between:

  1. Fuel and oil
  2. Radio power and battery life
  3. Potential energy (altitude) and kinetic energy (airspeed) Correct answer.
  4. Crew workload and passenger comfort

Explanation

Because gliders have no engine, soaring success depends on managing the exchange between altitude (potential energy) and airspeed (kinetic energy), plus harvesting energy from the air mass through lift. Smooth speed-to-fly technique conserves total energy.

Question 24Soaring aerodynamics, polar and loading

Which condition would most likely require dumping water ballast before continuing a cross-country flight?

  1. Strong, consistent thermals all afternoon
  2. A long final glide with a tailwind
  3. Smooth wave lift at high altitude
  4. Weak, deteriorating lift and the need to thermal slowly at low altitude Correct answer.

Explanation

Ballast helps in strong lift but hurts climb performance in weak thermals because of higher sink at low speed; when conditions weaken or the pilot must thermal slowly low to the ground, dumping water restores better climb and lower stall margin. Ballast should also be dumped before landing if required by the flight manual.

Question 25Soaring aerodynamics, polar and loading

A glider's published best glide ratio of 40:1 means that, in still air at best L/D speed, the glider will travel approximately:

  1. 40 feet forward for every 1 foot of altitude lost Correct answer.
  2. 1 foot forward for every 40 feet of altitude lost
  3. 40 nautical miles regardless of altitude
  4. 40 minutes of flight time

Explanation

A 40:1 glide ratio means 40 units of horizontal distance for each unit of altitude lost in still air at best L/D, so from 5,000 feet AGL the glider could cover roughly 40 times that height in distance, minus a safety margin. Wind shifts the effective ratio over the ground.

Question 26Soaring aerodynamics, polar and loading

What does a glider's never-exceed speed (VNE) placard represent for a commercial glider pilot?

  1. The best speed for thermalling
  2. The minimum sink speed
  3. The recommended approach speed
  4. The maximum speed that must never be exceeded in any operation Correct answer.

Explanation

VNE is the never-exceed speed; flying faster risks structural failure or flutter. The commercial pilot must respect VNE and the related maneuvering and rough-air speeds shown on the placards and in the flight manual.

Question 27Soaring aerodynamics, polar and loading

While thermalling, the technique of adjusting the circle so the glider stays in the strongest part of the lift is called:

  1. Speed to fly
  2. Final glide
  3. Energy dumping
  4. Centering the thermal Correct answer.

Explanation

Centering means adjusting bank, position, and timing so the circle is kept in the core of the thermal where climb is strongest, using variometer and feel; well-centered thermals dramatically improve climb rate and cross-country speed.

Question 28Soaring aerodynamics, polar and loading

On a cross-country task, why do experienced pilots often only stop to climb in thermals that are at least as strong as their MacCready setting?

  1. Weaker thermals are illegal to use
  2. Stopping for weak lift below the MacCready value lowers the achieved average cross-country speed Correct answer.
  3. Strong thermals damage the glider
  4. Weak thermals always contain hail

Explanation

Speed-to-fly theory shows that stopping to climb in lift weaker than the current MacCready setting reduces the overall average speed; pilots generally press on to find lift that meets or beats the set climb rate. The setting is adjusted as conditions change.

Question 29Soaring aerodynamics, polar and loading

A glider final glide is the:

  1. First climb after launch
  2. Mandatory go-around
  3. Calculated descent from the last thermal to the destination/finish, flown at the speed-to-fly for the conditions Correct answer.
  4. Cable-break recovery

Explanation

The final glide is the planned glide from the last climb directly to the goal or finish line, flown at the appropriate speed-to-fly and with an altitude safety margin; misjudging it is a common cause of landouts short of the goal.

Question 30Soaring aerodynamics, polar and loading

Which factor MOST reduces the actual distance a glider can cover on a final glide compared with the still-air computer prediction?

  1. A new coat of paint
  2. Lower outside air temperature
  3. Using the audio variometer
  4. A strong headwind and/or widespread sink along the route Correct answer.

Explanation

Headwind and sinking air both reduce ground distance covered per foot of altitude lost, so pilots add altitude margin and recompute final glides for wind and expected sink to avoid arriving low or landing out short.

Question 31Soaring aerodynamics, polar and loading

What is the recommended general technique for the highest energy-loss, steepest safe approach when a glider is much too high and spoilers/slip are still insufficient?

  1. Increase airspeed far above VNE
  2. Combine full spoilers with a forward slip (as permitted by the flight manual) to maximize drag without excessive airspeed Correct answer.
  3. Retract the gear
  4. Add positive flaps and float

Explanation

Combining full spoilers with a forward slip (when allowed by the specific glider's flight manual) produces the steepest controlled descent without an unsafe airspeed increase, helping recover a very high approach. Always confirm the maneuver is approved for the type.

Question 32Soaring aerodynamics, polar and loading

What is the principal performance reason a sailplane has very long, high-aspect-ratio wings?

  1. To reduce induced drag and achieve a high lift-to-drag ratio for efficient gliding Correct answer.
  2. To increase the stall speed
  3. To make ground handling easier
  4. To increase the minimum sink rate

Explanation

High aspect ratio reduces induced drag for a given lift, improving the lift-to-drag ratio so the sailplane can glide long distances and climb efficiently in weak lift; this is fundamental to soaring performance.

Question 33Soaring aerodynamics, polar and loading

Adverse yaw is especially important to manage in gliders because:

  1. Gliders have very short wings
  2. The long wings produce significant adverse yaw, so coordinated rudder use is essential to avoid uncoordinated stalls and slow rolls into turns Correct answer.
  3. Gliders cannot yaw
  4. Adverse yaw only affects powered aircraft

Explanation

Long-span glider wings generate pronounced adverse yaw when ailerons deflect, so the pilot must apply coordinated rudder during turn entry and exit; failure to do so leads to skidding/slipping and increases stall/spin risk while thermalling.

Question 34Soaring aerodynamics, polar and loading

When circling tightly in a thermal at a steep bank angle, the stall speed:

  1. Decreases compared with wings level
  2. Stays the same regardless of bank
  3. Increases because load factor rises with bank angle Correct answer.
  4. Becomes zero

Explanation

In a level turn the load factor increases with bank angle, and stall speed rises with the square root of load factor; tight thermalling turns therefore raise the stall speed, so the pilot must maintain an adequate speed margin to avoid an accelerated stall.

Question 35Soaring aerodynamics, polar and loading

Why does a commercial glider pilot recompute weight and balance when adding a heavy passenger or instructor in a two-seat glider?

  1. Adding occupant weight can shift CG outside limits and change stall/handling, which must remain within the placarded envelope Correct answer.
  2. Weight and balance never changes in gliders
  3. Only the towplane weight matters
  4. CG only matters for powered aircraft

Explanation

Occupant and ballast placement changes the CG; an out-of-limits CG degrades stability and spin recovery, so the pilot must verify the loaded CG and weight stay within the glider's placarded envelope before flight.

Question 36Soaring aerodynamics, polar and loading

If a two-seat training glider has a forward CG limit and is flown solo from the front seat with no rear ballast, the pilot should:

  1. Ignore CG since solo flight is always within limits
  2. Check whether minimum cockpit load or trim/tail ballast is required by the flight manual to stay within the forward CG limit Correct answer.
  3. Add water ballast to the wings
  4. Fly only at VNE

Explanation

Many gliders specify a minimum front-seat pilot weight or required trim/tail ballast for solo flight to keep the CG aft of the forward limit; the commercial pilot must follow the flight manual placards rather than assume solo flight is automatically in limits.

Question 37Soaring aerodynamics, polar and loading

In speed-to-fly practice, encountering sink between thermals should prompt the pilot to:

  1. Slow down and circle in the sink
  2. Maintain minimum sink speed
  3. Deploy spoilers
  4. Increase speed to transit the sinking air quickly and minimize altitude loss Correct answer.

Explanation

Speed-to-fly theory says to fly faster in sinking air to spend less time in it and reduce total altitude lost, then slow again in rising air; circling in sink would waste altitude and time.

Question 38Soaring aerodynamics, polar and loading

Why must a commercial glider pilot respect the maximum aerotow speed and the glider's rough-air/maneuvering speeds in turbulence?

  1. Faster is always safer in turbulence
  2. Exceeding these speeds in turbulence or on tow can overstress the airframe or cause control problems Correct answer.
  3. Speed limits do not apply to gliders
  4. Only VNE matters and nothing below it

Explanation

Operating above the maximum aerotow speed or above the rough-air/maneuvering speed in turbulence can impose loads beyond structural limits or cause control difficulties; slowing to the appropriate placarded speed protects the glider.

Question 39Soaring aerodynamics, polar and loading

A practical rule for choosing when to leave a thermal and continue on course is to leave when:

  1. The glider reaches VNE
  2. The variometer is turned off
  3. The climb rate falls well below the average usable climb for the day / current MacCready setting Correct answer.
  4. The passenger is bored

Explanation

Pilots generally leave a thermal as the climb weakens below the day's usable average or the MacCready setting, since continuing to climb slowly there lowers the overall cross-country speed; this is core speed-to-fly discipline.

Question 40Soaring aerodynamics, polar and loading

How does a tailwind affect the optimum speed-to-fly on a final glide compared with still air?

  1. The optimum speed increases
  2. The optimum speed decreases (fly somewhat slower) because the tailwind extends ground distance per foot of altitude Correct answer.
  3. Wind has no effect on final-glide speed
  4. The glider must fly at VNE

Explanation

A tailwind increases the ground distance covered per foot of altitude lost, so the speed-to-fly optimum shifts slightly slower than still-air best L/D; conversely a headwind shifts it faster. Pilots still keep a safe arrival margin.

Question 41Thermals, terrain lift and weather

A thermal is best described as which type of atmospheric lift?

  1. A rising column of air created by uneven solar heating of the surface Correct answer.
  2. Air deflected upward by a ridge or hill in wind
  3. A standing wave downwind of a mountain range
  4. Lift produced where two air masses converge along a sea-breeze front

Explanation

A thermal is a buoyant column or bubble of warm air that rises because the surface heated unevenly, making that air less dense than its surroundings. Thermals are the most common lift source for cross-country soaring.

Question 42Thermals, terrain lift and weather

Which atmospheric condition is most favorable for the development of strong, well-organized thermals?

  1. A surface-based temperature inversion
  2. A steep environmental lapse rate (unstable air) with surface heating Correct answer.
  3. A deep, moist stable layer
  4. Light winds with widespread stratus

Explanation

Strong thermals require an unstable atmosphere, meaning a steep environmental lapse rate so a rising parcel stays warmer than its surroundings and continues to ascend. Daytime surface heating provides the trigger.

Question 43Thermals, terrain lift and weather

Ridge (slope) soaring lift is produced when:

  1. The sun heats a plowed field
  2. Air sinks on the lee side of mountains
  3. Wind blows against a ridge or hill and is deflected upward along the slope Correct answer.
  4. Two surface air masses converge

Explanation

Ridge or slope lift occurs when wind strikes the windward face of a ridge or hill and is forced upward; a glider can soar along the ridge in this band of rising air as long as the wind has a sufficient component perpendicular to the ridge.

Question 44Thermals, terrain lift and weather

Mountain wave lift is characterized by which of the following?

  1. Disorganized, short-lived bubbles of warm air
  2. Lift only available near the surface
  3. Lift that requires strong surface heating
  4. Smooth, standing waves of rising and sinking air downwind of a mountain barrier in stable airflow Correct answer.

Explanation

Mountain (lee) waves form when stable air flows over a mountain barrier with sufficient wind speed, producing a series of smooth standing waves downwind; the rising portions can carry gliders to very high altitudes. Lenticular clouds often mark the wave crests.

Question 45Thermals, terrain lift and weather

A lenticular (cap) cloud aligned in a stationary lens shape downwind of mountains most strongly indicates the presence of:

  1. Mountain wave conditions Correct answer.
  2. Thermal activity
  3. An approaching warm front
  4. Fog formation

Explanation

Smooth, stationary lens-shaped (lenticular) clouds form at the crests of mountain waves where rising moist air cools to its dew point; they are a classic visual marker of wave lift and the associated turbulence in the rotor below.

Question 46Thermals, terrain lift and weather

The turbulent, rolling air mass found beneath and downwind of the primary mountain wave crest is called the:

  1. Inversion
  2. Rotor Correct answer.
  3. Thermal street
  4. Convergence zone

Explanation

The rotor is a zone of intense mechanical turbulence that forms below the wave crests, often marked by a ragged rotor cloud; it can be hazardous and must be respected when entering or exiting wave lift.

Question 47Thermals, terrain lift and weather

Which document or product gives soaring pilots a forecast of thermal strength, top of lift, and trigger temperature for a given day?

  1. A METAR
  2. A NOTAM
  3. A soaring (thermal) forecast or RASP/Skew-T analysis Correct answer.
  4. An aircraft weight and balance sheet

Explanation

Soaring forecasts, including products like RASP and a Skew-T sounding analysis, predict the trigger temperature, thermal strength, height of usable lift, and convergence, helping pilots plan cross-country tasks. METARs only report current surface conditions.

Question 48Thermals, terrain lift and weather

Two cumulus clouds line up in a long row along the wind, allowing extended straight-ahead climbing. This soaring feature is called a:

  1. Lenticular
  2. Cloud street Correct answer.
  3. Virga
  4. Cap cloud

Explanation

A cloud street is a line of cumulus formed along the wind by organized convection; gliders can fly straight along streets, climbing in the lift bands and covering distance with minimal circling. They typically form in moderate winds with good thermals.

Question 49Thermals, terrain lift and weather

Why should a glider pilot avoid flying directly through the lee-side rotor when attempting to enter mountain wave lift?

  1. The rotor contains the strongest smooth lift
  2. The rotor produces icing only
  3. The rotor is a zone of severe, possibly damaging turbulence Correct answer.
  4. The rotor is restricted airspace

Explanation

The rotor beneath the wave crest is intense mechanical turbulence that can exceed structural and control limits; pilots usually enter wave lift in smoother air, climbing the laminar wave rather than fighting through the rotor. Briefing rotor location and entry technique is essential.

Question 50Thermals, terrain lift and weather

Convergence lift along a sea-breeze or other air-mass boundary is useful to soaring pilots because it:

  1. Only exists at night
  2. Requires no wind at all
  3. Produces only sink
  4. Can form a long line of lift that allows extended straight-line soaring along the boundary Correct answer.

Explanation

Where two air masses with different properties meet, one is forced to rise along the convergence line, creating a long band of lift that gliders can exploit for fast straight-line cross-country runs, similar in usefulness to a cloud street.