BETA INTERACTIVE 3D WIND TUNNEL · CESSNA 172N CONCEPT

See what the air is doing to the airplane

Change power, elevator, flap setting, weight, wind, and turbulence. Indicated airspeed and altitude emerge from those inputs, while the diagram resolves the major forces, shows the approach to a stall, and models the consequences of prolonged high-altitude flight without supplemental oxygen.

Indicated airspeed

105 KIAS

04080120160200105KNOTS
GROUND SPEED

Groundspeed

105 KT GS

Vertical speed

0 ft/min

AUTO TRACK HOLD NO CRAB HDG 090° · TRK 090°

ALTITUDE

2,500FT MSL

LEVEL

STALL

LiftWeightThrustParasite dragInduced drag

SIDE VIEW · FORCE ARROWS SCALE RELATIVE TO ONE ANOTHER

STALL REFERENCE—

VERTICAL TREND—

LONGITUDINAL TREND—

FLAP LIMIT—

OXYGEN / PILOTNormal range · no supplemental O₂ requiredPHYSIOLOGY DEMO ×60

FLIGHT CONTROLS & CONDITIONS

Fly the airplane

Set power and configuration, then use elevator to manage the flight path. Airspeed and altitude are calculated outcomes—not direct controls.

Indicated airspeedCalculated from thrust, drag, pitch, gravity, flaps, and weight105 KIAS

Headwind / tailwind- tailwind · + headwind 0 kt 105 kt groundspeed

Crosswind- from left · + from right 0 kt Track held · no crab

Engine RPMPropeller thrust 2,300 RPM

96 hp · 241 lb modeled thrust

Elevator deflection23° down · 0° aligned · 28° up; neutral surface is not a level-flight command 0° NEUTRAL

Flaps

Actual 0.0° · selected 0°172N reference range.

Landing gear comparison

Gear drag is being calculated…

Teaching comparison only: the displayed Cessna 172N normally has fixed landing gear. “Gear up” demonstrates how a comparable retractable-gear configuration changes performance.

Coordinated flight · 0° sideslip

Aircraft weightChanges wing loading and stall speed2,300 lb

TurbulenceColored gust field: calm to strongCalmCalm air · Dryden-style gust model begins at zero energy

What should I try?

Notice that 0° elevator only means the surface is aligned with the stabilizer. It does not guarantee level flight after power, speed, weight, flap, or gear changes; use Set level-flight trim to find the required setting.
Reduce RPM and watch thrust fall, airspeed decay, and the airplane settle into a glide descent.
Raise the nose and watch altitude, airspeed, angle of attack, and the 1-G stall-speed reference trade against one another.
Notice that low speed at modest angle of attack causes insufficient lift and descent—not a stall. The stall warning appears only as the wing approaches its modeled 16° critical angle of attack.
Lower the nose in a power-off glide and watch airspeed recover as altitude decreases.
Press and hold the forward-slip control; watch the left and right ailerons move oppositely while the rudder crosses against the bank, then compare the added parasite drag, reduced effective lift, steeper descent, and lower efficiency. Release it to coordinate the airplane again.
Select each flap setting and watch both physical flap surfaces move to the commanded angle before comparing lift and drag.
Hold power and elevator steady, retract the comparison gear, and watch parasite drag fall before speed, lift, and vertical trend find a new balance.
Pull abruptly at higher airspeed to see load factor and accelerated-stall risk.
Use high power while descending to approach the red-line speed and overspeed warning.
At high altitude, watch the oxygen panel progress from an FAA use-limit warning to impaired performance and incapacitation. Its physiology clock runs 60 times faster than real time for demonstration.
This 172N model offers 40° maximum flap deflection.

MODEL-BASED RANGE EFFICIENCY

See where each gallon’s energy goes

This is no longer a weighted teaching score. The powered index comes directly from modeled lift-to-drag ratio × propeller efficiency ÷ brake-specific fuel consumption, normalized to this model’s clean best-range condition. With the engine stopped it reports aerodynamic glide efficiency.

Efficient

POORFAIRBEST 75RELATIVE RANGE
EFFICIENCY

Adjust one control at a time and watch what changes.

Aerodynamic L/D—

Live lift divided by total modeled drag, compared with the clean drag-polar maximum.

Drag crossover—

A direct ratio reaches 100% only when induced and parasite drag are equal.

Propeller efficiency—

Useful thrust power divided by engine shaft power at the current airspeed.

Engine fuel conversion—

Brake-specific fuel consumption: fuel mass used per horsepower-hour. Lower is better.

Relative range efficiency—

The direct propeller-aircraft range result relative to this model’s clean best-range condition.

INDUCED DRAG—

PARASITE DRAG—

Move toward the crossover where the two drag components match.

Ground speed—Statute miles per hour over the ground; wind and crab can change this without changing indicated airspeed.

Ground MPG—Statute ground miles traveled per gallon at the current groundspeed and fuel flow.

Fuel flow—Modeled gallons used per hour at the selected RPM.

Endurance per gallon—Hours and minutes of engine operation represented by one gallon at the current fuel flow.

Air range—No-wind nautical air miles per gallon, kept separate from wind-affected ground MPG.

Lift-to-drag ratio—Live aerodynamic lift divided by parasite, induced, and RMS gust drag.

The index is a direct relative result from the simulation’s aerodynamic, propeller, and fuel-flow model—not a weighted opinion score. Wind changes range over the ground but does not change the airplane’s own energy conversion, so the index uses airspeed. It is not a POH range prediction or fuel-planning value.

AIRSPEED—KIAS

ANGLE OF ATTACK—°

LIFT—lb

WEIGHT—lb

THRUST—lb

PARASITE DRAG—lb

INDUCED DRAG—lb

WING LOADING—lb/ft²

LOAD FACTOR—G

GUST LOAD—G

WHAT THE MODEL IS CALCULATING

One force picture, several different limits

Lift and load factor

Dynamic pressure, wing area, actual intermediate flap position, and angle of attack determine the modeled lift. The tracked single-slot flaps take time to move, so lift, drag, stall speed, and pitching moment change continuously during extension or retraction rather than jumping when a button is selected. Lift divided by weight produces load factor. A 2 G pull requires roughly twice the lift and raises stall speed. The elevator control uses the 172N’s published 28° up and 23° down surface travel; wing angle of attack is a separate calculated result, not the elevator angle.

Two kinds of drag

Parasite drag rises rapidly with airspeed and exposed landing gear or flap extension. Induced drag is the lift-related cost of producing lift and becomes most important at low speed and high lift coefficient.

Approach to the stall

The displayed stall speed is a 1-G reference, not a stall switch. Lower speed reduces dynamic pressure, so maintaining altitude requires progressively more angle of attack. The warning begins only as the wing approaches the modeled 16° critical angle. At the break, airflow separates, lift drops rapidly—but not to zero—and the trainer pitches nose-down into a continuing descent. Recovery begins only after the pilot lowers angle of attack below the critical angle long enough for airflow to reattach; raising the nose too soon can cause a secondary stall.

Power, propwash, pitch, and airspeed

Pitch is no longer a hand-set visual offset. The model sums the 172N’s angle-of-attack stability, elevator control power, pitch-rate damping, thrust-line moment, and pitch inertia. Changing RPM changes thrust and its pitching moment; NASA actuator-disk momentum theory then calculates the propeller’s induced airflow from thrust, propeller diameter, air density, and present airspeed. That added dynamic pressure is applied only to the root-wing area and tail inside the slipstream—not to the complete wing—so powered local lift, induced drag, and elevator authority change together. Published Cessna 172N performance anchors and the shared propeller momentum model drive thrust, propwash, pitch response, airspeed, and altitude.

Turbulence and buffet

The turbulence selector now drives a Dryden-style colored-gust field instead of arbitrary motion. Longitudinal, lateral, and vertical gust velocities use RMS intensity, altitude-dependent scale length, and the airplane's speed through the air mass. Vertical gust velocity changes angle of attack and load; lateral gust velocity drives the roll and control response. Stall buffet uses a separate short-scale filtered component, so the shaking is irregular but does not create imaginary lift or altitude.

Forward slip

The slip control no longer assigns a fixed angle or minimum descent rate. Published 172N lateral stability and control derivatives solve the crossed rudder and opposite-aileron balance. The resulting sideslip creates a calculated side force, which sets the wing-low bank needed to hold the original ground track. Exposed side area and dynamic pressure determine the added drag; that drag’s power then removes altitude energy from the same flight model. More airspeed, more crossed control, and aircraft weight therefore change the result naturally.

Altitude, oxygen, and hypoxia

Without supplemental oxygen, the panel follows the FAA operating thresholds: required crew must use oxygen after 30 minutes from 12,500 through 14,000 feet pressure altitude, and continuously above 14,000 feet. Impairment is progressive—not an instant boundary—and varies widely. To make that progression observable, one real second represents one minute on the physiology demonstration clock. Severe exposure causes modeled pilot incapacitation, a time-compressed uncontrolled descent, and ground impact. The extreme-altitude range exists to teach physiology; it does not imply that this normally aspirated 172N can climb to those altitudes.

REPRESENTATIVE TRAINING MODEL

Useful for concepts—not aircraft operation

The geometry and limits represent a legacy Cessna 172N-style landplane: 174 ft² of wing area, 2,300 lb maximum weight, 160 hp at 2,700 RPM, 40° maximum landing flap deflection, and a red line near 160 KIAS. Performance anchors come from its POH: 50-knot clean and 44-knot full-flap power-off stalls, 65 KIAS best glide, 770 ft/min maximum sea-level climb at 73 KIAS, and the published 2,000-foot cruise table. A 172N has fixed landing gear; the gear selector is an explicitly hypothetical comparison. This remains an educational approximation—not a POH, performance calculator, or substitute for instruction.

Model basis: Published Cessna and FAA operating data anchor the envelope and performance. Published UIUC/NASA derivatives and standard equations supply the dynamic model. Explicit training thresholds remain educational methodology rather than aircraft certification data.

Read forces in the PHAK Read about stalls Load factor and stalls Cessna 172N POH extract FAA Type Certificate 3A12 UIUC Cessna 172 dynamics data FAA slips guidance NASA propeller momentum theory NASA Dryden turbulence reference FAA hypoxia guidance