*Stall speed KCAS is a function of (depends on): (Circle all correct answers. Something traveling at one kilometer per hour is traveling about 0. The minimum speed is 210 kts. Expert Help. T F Stall KCAS increases as altitude increases. a) increase during a climb. • Silent 14cm fan with optimized thermal fan speed control • Powerful single +12V rail offers compatible DC outputThe SI derived unit for speed is the meter/second. The ground speed (GS) is how fast the aircraft is actually moving over the ground and is what affects the total flight time. c) The airspeed indicator, altimeter, and Vertical Speed Indicator. Also, explore many other unit converters or learn more about speed unit conversions. Flight Envelope The flight envelope is defined in the applicable EASA approved Aircraft Flight Manual; referenced inTop Speed: 186 KCAS; Cruise Speed: 148 KCAS; Stall Speed (Landing Configuration): 55 knots; Stall Speed (Clean): 60 knots; Fuel Consumption: 9. Maximum autopilot operating speed. *For a given aircraft in a given configuration, stall KCAS changes when _____ changes (at least three factors). At airspeeds above 187 KCAS, the roll induced by a full rudder deflection could be corrected by control wheel input; however, in the same. 67 KCAS c C. 70 KCAS. There will be a climb speed schedule the airplane is following, such as for the A32NX normally is 290KCAS/M0. Calibrated airspeed in knots is usually abbreviated as KCAS, while indicated airspeed is abbreviated as KIAS. The 150 would have Vs0 41 KCAS, so the same. Vmcg (Minimum control speed Ground): 89 KIAS (92 KCAS) Vlo (landing gear operating) Extending: 186 KIAS (185 KCAS) Retracting: 175 KIAS (172 KCAS) Vle (Landing Gear Extended: 186 KIAS (183 KCAS) Vsb (speed brakes extended): Any speed with or without flaps. We can confidently guide our clients to ensure them that they are conducting their studies in the most effective way to assess on-target and off-target biodistribution. Once past the 1,500’ show line, bank angle can be increased to capture and maintain 500. Thus, v can be treated as a function of y only, y being treated as the independent variable. BRISTELL RG Photogallery. JustAnotherJodieFE. Maximum Limit Speed: 210 kias (389 km/h) Stall Speed: 74 kcas (137 km/h) Powerplant. Rotor Speed Limitations Power on: Maximum 104 % (530 rpm) Minimum 97 % (495 rpm) Power off: Maximum 110 % (561 rpm)The speed in feet per second is equal to the speed in knots multiplied by 1. Indicated airspeed (IAS) measures speed along with. “When you crossed 6,000, I was showing 5,920,” Filucci said. Calculate the Dynamic Pressure 'q' [lb/ft2], based on the TAS above. While not an airspeed, GS is important for navigation and has a major impact on the time it takes to get to a destination. Mach is the ratio of an object's speed to the speed of sound. The KCAS PLUS GOLD is 80Plus Gold Certified for up to 92%+ efficiency, delivering maximum efficiency performance. Common abbreviations: kn, kt. 10. Extended Speed V. Maximum structural cruising speed (V NO) is 147 kcas. Sea level to 30,500 feet: 263 KIAS (260 KCAS) Base Price: $154,900: Typically Equipped Price: $159,245: Engine: Lycoming O-235-K2C: Horsepower: 118 hp: Propeller: Sensenich (2 blade) Seats: 2: Length: 22 ft. 90712743552 kt. VA Maneuvering speed 1450lbs. 151 mph or 0. (use only for Non-Standard Day) Kelvin [K] Celsius [°C] Fahrenheit [°F] Rankine [°R] Results. b) The airspeed indicator and the altimeter. Sea level to 30,500 feet: 263 KIAS (260 KCAS) Above 30,500 feet: 0. Increase of stall speed (which they estimate will indirectly limit MTOW to 3000lb) Expand LSA to apply to all classes of aircraft. The KCAS PLUS M is 80Plus Bronze certified for high performance with up to 85%+ efficiency. You have to slow from flare-entry speed to just above stall – say, 50 KCAS in a 172 with a 46 KCAS stall speed. Enter the flare in a 172 at 65 knots instead of 60 and. 119 KIAS (117 KCAS) TO . Useful Load: 1,559 lbs. 3048 meters per second, or about 0. Speed limit: Main Wheel Steering Nose Wheel Tire. 87M were entered on the Performance Initialization menus. 27. A. 06 518 . MOD2002/29, or equivalent Service Bulletin n. There have historically been different nautical miles used and, thus, different variations of knots. Something traveling at one knot is going about 1. [G450 Aircraft Operating Manual, §07-02-30-03-40; ¶ 3. Mach number and knots are both units used to measure speed. Common abbreviations: km/h, kmph, km/hr, km/hour. A fan speed of 45% and a longitudinal stick position of about 41% should maintain this condition with a pitch attitude of 2O nose-down. Maximum Limit Speed: 182 kias (337 km/h) Stall Speed: 57 kcas (106 km/h) Powerplant. Above 41,000', Min Speed 0. for 85%+ efficiency • Equipped with DC-to-DC conversion circuit • Silent 12cm fan with optimized thermal fan speed control • Powerful single +12V rail offers compatible DC output • Complete over current protection and over temperature. Our calculator rounds at 3 decimal places, in this case 197. DOWNLOAD Brochure Now. kt meters per second . KTAS or Knots True Airspeed is the airspeed of the airplane relative to the (stationary) air, it is flying through. Adjusting the approach speed based on a lower stall speed. Share. According to the manufacturer, the new fighter attack version is an evolution of a family concept of the M. 316 (1) A maximum stalling speed or minimum steady flight speed without the use of lift-enhancing devices (V S1 ) of not more than 45 knots CAS, except for airplanes, which must have a V S1 speed of not more than 54 knots CAS at the aircraft's maximum certificated takeoff weight and. 77 Mach or 504 Miles per Hour (MPH) Airspeed Limits: See KCAS note at top V MO (Maximum Operating Speed) VMO. Added manual, realistic and KCAS wheel attribute modes; Added manual luck mode; Added unleveled, retroactive and unchanged health modes; Added various sleeping modes; Added ability to configure the speed of individual skills; Updated xp calculation for various actions like quests, repair items and trainingThat's the difference. Stepping into the Cardinal is more like sliding into a sedan than climbing into a pickup. It is one of the best place for finding expanded names. The Cytek Aurora instruments have several software and hardware features that allow direct communication between groups and minimize the differences between. mach (speed of sound) 0. 1 million: Typically Equipped Price: $1. Uses 1976 US Standard Atmosphere definitions. The IAS is typically used for low speeds and low altitudes. At low speed, near the stall, 40 KIAS (the low end of the white arc) and 48 KCAS (Vs0 in the POH) refer to the same actual speed. 514 m/s ). Total up the minutes flying + the fuel reserve = 137 minutes. 141 KTAS. Kilometers per Hour. Max Speed (Vh): 95 KCAS (109 mph) (176 kph) Range: 427nm (45 min reserve) Takeoff Distance Runway 640 ft / Water 840 ft. KCAS Bioanalytical and Biomarker Services, an Integris BioServices, LLC Company is a rapidly growing company that provides comprehensive GLP / GCP compliant development services from early discovery support through product registration and beyond. Cancel Max Reverse By. Sea Level: 263 KCAS; 26,000 Feet: 297 KCAS; 31,000. This puts you near the bottom of the total drag curve. Post Jan 15, 2006 #8 2006-01-15T22:53. A. 3 Vs0 is 56 knots. The conversion factor between knots and MPH is 1 knot equals 1. How do you convert KIAS to KTAS? Use your KCAS/KIAS and for each thousand feet you add 2%. 51444444444 mps Conversion base : 1 kt = 0. According to the CTLS Pilot. 6 seconds) can determine the size of the circle; 202. If the gross weight of an aircraft without cargo is 500,000 pounds and the stall speed at that weight is 120 KCAS, what is the new stall speed KCAS when 500,000 pounds of cargo is added, i. Calculate the distance from what would hear sound after 10 seconds. Base Price: $154,900: Typically Equipped Price: $159,245: Engine: Lycoming O-235-K2C: Horsepower: 118 hp: Propeller: Sensenich (2 blade) Seats: 2: Length: 22 ft. Seattle, Washington 981242207- . Maximum Cruise Speed. 78-0. 3 inches and 2,500 rpm, while burning 32 gallons per hour. Groundspeed is used by pilots when making time and distance calculations. So if you're climb at a constant Mach, like your first example at M2. 6 equals 13,912 feet. Knots are a speed measurement that is nautical miles per hour. There have historically been different nautical miles used and, thus, different variations of knots. As discussed earlier, analytically, this would restrict us to. Not bad for a 150-hp airplane. The 77 cubic ft capacity factory installed system will provide plenty of oxygen for all occupants in normal flight durations. The KTAS (knots true airspeed) is very important for accurate navigation of an aircraft. 106. The Boeing 747-8 Intercontinental and 747-8 Freighter are the new, high-How does the stall speed (KCAS) vary as you climb from sea level to 33,000 feet? It remains relatively unchanged throughout the climb. Indicated airspeed (IAS) measures speed along with changes in pressure. It was introduced in Europe in 1979 as a lower cost alternative to the Tobago, but didn't appear in the United States until 1985; since then, about 300. Study with Quizlet and memorize flashcards containing terms like Speed: Gear, Speed: Main tire, Speed: nose wheel and more. Vote. The family’s cruise speed is set at 104 KCAS. 78. Originally powered by a 260-horsepower Lycoming, it evolved quickly to a 300-hp engine. The RV–10’s altitude advantage at 6,000 feet is less than 100 feet. Air Speed Indicator; Pitot Static System; Categories. 225 = 68. Scientists and Engineers refer to Airspeeds as ‘V’ Speeds. An aircraft’s indicated airspeed in knots is typically abbreviated KIAS for “Knots-Indicated Air Speed” (vs. Calculating off of KIAS gives you a speed that's a whole 10 knots too slow! PS: From my personal experience of about 150 hours on 152s, a final approach speed of 60-65, depending on conditions, is perfectly fine. Knots True Airspeed (KTAS) is different than indicated airspeed. Mach Speed. 3. The Cessna 185 first appeared in 1961 as an evolutionary follow-on to the popular 180. Your groundspeed will be higher, and the same as your KTAS in zero wind as well. To maintain a desired. 3. The relationship between airspeed and ground speed is fairly simple. AI Homework Help. More Information. 6 m/s. 2 KCAS Vm Minimum level flight speed Not Applicable Vx Speed for best angle of climb 60. 738661. 278 meters per second, or about 0. 23 seconds decel time from 160 KCAS to 140 KCAS. In this case we find our 1g stall speed, at 1800 lbs. 340 KCAS above 8,000 feet. 3 meters per second. The true airspeed (TAS; also KTAS, for knots true airspeed) of an aircraft is the speed of the aircraft relative to the air in which it is flying. Calibrated airspeed in knots is usually abbreviated as KCAS, while indicated airspeed is abbreviated as KIAS . Multiply the KIAS value by the conversion factor (1. Air speeds Design Maneuvering Speed V A: 119 KIAS (117 KCAS) Flap Extended Speed V FE: 93 KIAS (92 KCAS) LND 119 KIAS (117 KCAS) TO Minimum Control Speed V MC: 62 KIAS (62 KCAS) Maximum Landing Gear Operation speed V LO: 93 KIAS (92 KCAS) Maximum Landing Gear Extended Speed V LE: 93 KIAS (92 KCAS) Maximum Structural Cruising Speed V NO VEAS = √2qc ρ0 = √2 ⋅ 2879. Clean stall speeds are nearly identical across the three – 50 KCAS for both the Cessna 172F and 172N, but 51 KCAS on the 172R. 7 degrees per 0. VMCA Minimum control speed in air 105 KCAS VMCG Minimum control speed on the ground 90 Kts VLO Landing gear maximum operating speed 155 KCAS VLE Extracted Landing gear maximum operating speed 200 KCAS VFE Maximum speed FLAPS 1 180 KCAS Maximum speed FLAPS 2 170 KCAS Maximum speed FLAPS Full 155 KCAS VA Manoeuvre speed at 30500 Kg (67240 lbs. c130herculesheadquarters. Calculate standard and non-standard atmosphere properties and speed conversions. Gust load speed (turbulence penetration) 90 KCAS: 86 KIAS: 120 KCAS: 120 KCAS: 90 KCAS: 87 KCAS: Airspeed limitation with equipment carried on external pods* 108 KCAS: 108 KCAS: 108 KCAS: 108 KCAS: 108 KCAS: 108 KCAS *before the GVT and flight tests are performed. Study with Quizlet and memorize flashcards containing terms like Gross weight with fuel and 2 souls, One engine thrust MIL, One engine thrust MAX and more. A. Knowing the speed in fps (202. Mach. 98. For example, an aircraft cruising at 12,000 msl with 166 KCAS travels around 200 KTAS. This unit is typically used in maritime and aviation. 477322 kn . e. Common abbreviations: kn, kt. Real World Target: 23 seconds. and the 250 calibrated airspeed in knots (KCAS) speed limit in the United States and in. T F Stall KCAS does not change with altitude changes. Landing Gear Extend Speed. If the mass is increased to 2000 kg , the new value of the stall speed will be ; a) 123 kt. 8) multiplied by the time an aircraft takes to complete a circle (68. KIAS is. Common abbreviations: kn, kt. 131 KTAS. Takeoff Field Length. Mach is the ratio of an object's speed to the speed of sound. Max. A few have flaps, but it’s not the normally taken approach. 3. 145 KTS . This section requires altitude only. 10. The minimum speed is in accordance with the chart in expanded limitations procedures of Planebook. Its all-composite hull is resistant to extreme environments, even when the aircraft is left in saltwater. KCAS:95 KIAS:97. Cruise Recommendations: A lean mixture w/fuel allowance for engine start, taxi, takeoff, climb and 45 minutes reserve. Groundspeed is the speed of the aircraft in relation to the ground. The Dassault Falcon 20 is a French business jet developed and manufactured by Dassault Aviation. Although indicated airspeed (IAS) and true airspeed (TAS) are the speeds most commonly used in aviation, references to calibrated airspeed (CAS) and equivalent. What is the stall speed when the weight is 5,000 Ibs? a A. 7. Something traveling at one knot is going about 1. V LE Maximum Landing Gear Extended Speed is the maximum speed at which an airplane can be safely flown with the landing gear extended. 29 million: Engines: Austro AE330: Horsepower Per Side: 180 hp turbodiesel: Propellers: MT (3 blade) Seats You have to slow from flare-entry speed to just above stall – say, 50 KCAS in a 172 with a 46 KCAS stall speed. Although KTAS and IAS can be. So if we are at 25,000 feet and cruising at 300 KIAs, then 2% times 25 equals. Knots are a speed measurement that is nautical miles per hour. Alternatives include the Beech Bonanza, Mooney. 1%. Calculating off of KIAS gives you a speed that's a whole 10 knots too slow! PS: From my personal experience of about 150 hours on 152s, a final approach speed of 60-65, depending on conditions, is perfectly fine. These are shown in Fig. For 15,000 feet max AB, your best performance is between 400-450 KCAS (0. [3] An aircraft's indicated airspeed in knots is typically abbreviated KIAS for " Knots -Indicated Air Speed" (vs. 88 IMN) with about 0. -2. But it is important to note that there are three distinct types of airspeeds: Knots Indicated Airspeed (KIAS) Knots Calibrated Airspeed (KCAS) The RV–10 climbs at a slightly steeper angle, and the SR22 delivers more forward speed. 1). H342 IRA (Refer to figure 32. Min 1500PSI Max 3200PSI Normal Range 2850-3200PSI. Free online speed converter - converts between 33 units of speed, including meter/second [m/s], kilometer/hour [km/h], mile/hour [mi/h], break, etc. How do you convert KIAS to KTAS? Use your KCAS/KIAS and for each thousand feet you add 2%. Above 41,000', Min Speed 0. The maximum speed is 250 KCAS. 2. It is equal to exactly 1. 6%. 151 land miles per hour. Yaw damper inoperative speed (minimum): Below 20,000 ft. Another factor to consider is the speed of sound. Two airports Two airports are 2690 km away. 225 = 68. 0, then the M is the highest speed, and the rest decrease accordingly with altitude, so big picture, this is correct performance. ] Recommended turbulence penetration airspeed is 270 KCAS / 0. While there is a limited divergence (0 to 2%) between CAS and IAS at medium and high speed, this difference can be as much as 20% at low speed, when the aircraft pitch is large. Feedback. Air Speed Limitations V NE (never exceed) Power-on and Power-off 98 KCAS sea level to 3 000 ft DA, decreasing to 83 KCAS at 8 000 ft DA, decreasing to 56 KCAS at 14 000 ft DA. Max Cont TGT. KCAS is listed in the World's most authoritative dictionary of abbreviations and acronyms. Piper Apache. 3. Per 61. CRUISE Using recommended lean mixture with fuel allowance for engine start, taxi, takeoff, climb and 45 minutes reserve. Based on the 1976 US Standard Atmosphere (NASA-TM-X-74335) methodologies and valid through 20 km (stratopause) for atmospheric flight calculations (identical to ICAO and International Standard Atmosphere definitions. The “V” is from the French word ‘Vitesse’ which means ‘speed’ or ‘rate’. 75 MT, whichever is lower. 6 m/s (133 knots) despite the fact that you are moving with 75 m/s (146 knots) with respect to the air. 0. These are shown in Fig. 610 deg C. LO: 93 KIAS (92 KCAS) Maximum Landing Gear . 540 deg C. not make full or abrupt control movements above this speed. Updated 25 Aug 2022 Learn with flashcards, games, and more — for free. ) Substituting v for dy dt and vdv dy for d2y dt2 in the original equation gives the following ODE: yvdv dy + v2 = 0. [1] Practical applications of CAS CAS has two primary applications in aviation: Calibrated airspeed (CAS) is the IAS corrected for instrument and position error. 85 M 41,000' Max if Single Bleed. Study with Quizlet and memorize flashcards containing terms like What is the minimum climb rate for instrument departures?, If you go missed approach on a circling approach, which missed approach procedure do you fly?, What. Your airspeed indicator (assuming no errors) will read only 68. 8 1. As long as no external air forces are present, the true. Comes equipped with DC-to-DC conversion circuit for more reliable operation with heavy CPU and GPU loads. b) 150 kt. SPL Vh limit removed. The Italian-based international defense company Leonardo is introducing a new, Fighter Attack (FA) variant of their M-346 trainer, dedicated to attack missions. Knots Calibrated Air Speed. Maximum Degraded Flight Controls Speed. 1%. At airspeeds above 187 KCAS, the roll induced by a full rudder deflection could be corrected by control wheel input; however, in the same configuration at airspeeds of 187 KCAS and below, the roll induced by a full rudder deflection could not be completely eliminated by full control wheel input in the opposite direction, and the airplane. Based on the 1976 US Standard Atmosphere (NASA-TM-X-74335) methodologies and valid through 20 km (stratopause) for atmospheric flight calculations (identical to ICAO and International Standard Atmosphere definitions. 260 KCAS up to 15,000 ft. Or sign in with one of these services. 57 A Where A ’altitude (K ft) 8-2. In aviation, equivalent airspeed ( EAS) is calibrated airspeed (CAS) corrected for the compressibility of air at a non-trivial Mach number. 4. In this case we find our 1g stall speed, at 1800 lbs. Keep in mind the instructions said the given lift-off speed is 150 KTS. Fuel Burn: 34 gph: Max Speed: 202 ktas: Max. 02 IMN. High Speed: Airplanes with a V C or V MO > 250 KCAS (and M MO > 0. Rating: 3. Two airports Two airports are 2690 km away. 75 MT, whichever is lower. Uses of true airspeed. Unlock. Calibrated airspeed in knots is usually abbreviated as KCAS, while indicated airspeed is abbreviated as KIAS. KCAS is the most well-suited provider to offer PCR because of our all-new state-of-the-art facilities, our experience, our expertise, and our understanding of quality regulations. 151 land miles per hour. 6. Max TGT Overtemp. ROTAX 915 iS. Useful Load: 1,559 lbs. Never exceed speed. 777-300 stall speed at max t. The KCAS PLUS is 80Plus Bronze certified for high performance with up to 85%+ efficiency. Study with Quizlet and memorize flashcards containing terms like KIAS, KCAS, KTAS and more. Speed: 126 knots Maximum at sea level. 221 (14 ply) ktsGS 195 (12 ply) ktsGS 174 ktsGS. 154 KCAS. Something traveling at one knot is going about 1. Durability. 3 buffer brings that to 269 kts. For v ≠ 0, I will solve the ODE above for v (by. Obviously the TAS (true air speed) increases with the pressure altitude. Knots to Meters per second. そのため航空機の 速度 は大気との相対速度である対気速度を計測している。. Find the Calibrated Lift-Off Speed [KCAS] using the chart below, whichKnots Indicated Airspeed is the speed shown on the airspeed indicator and expressed in knots. Indicated airspeed (IAS) is what you read off the airspeed indicator as you fly. 5. 1 Answers. For a more accurate answer please select 'decimal' from the options above the result. This is because mass is defined by L and ρ p (both are included), and weight is defined by L, ρ p, and g (all three are. If that C172P is at 2100 lb, then sqrt(2100/2400) is . Indicated Air Speed can be displayed by selecting ‘Yes’ for ‘Indicated air speed’ under the Interface tab of Game Options. KIAS vs KCAS vs KTAS; 1. What does KCAS abbreviation stand for? List of 24 best KCAS meaning forms based on popularity. General, Theory of Flight. The retractable landing gear improves the already excellent speed characteristics, and the stretched fuselage allows a more efficient use of cabin space,. The KCAS PLUS GM is 80Plus Gold certified for high performance with up to 90%+ efficiency. It will then be shown in the HUD as ‘IAS’. 221 (14 ply) ktsGS 195 (12 ply) ktsGS 174 ktsGS. Its all-composite hull is resistant to extreme environments, even when the aircraft is left in saltwater. 6%. 75 kcas: Stall speed, full flaps (35°), ISA, MTOW, seal level: 128 km/h: 69 kcas: Maximum approved altitude: 7620 m: 25000 ft: Single engine service ceiling ISA, MTOW: 2133 m:Knots True Airspeed (KTAS) is different than indicated airspeed. Maximum Degraded Flight Controls Speed. This difference is more pronounced in. 4 gallons per hour at 75% power; Range: 550 nautical miles; Service Ceiling: 15,000 feet; Landing Ground Roll: 776 feet; Landing Over 50 ft. 3. Miles per Hour. Get a 1 dash 1, all your answers lay within. 621 miles per hour. KCAS - What does KCAS stand for? The Free Dictionary. The shape of KCAS curves may result from low speed buffet boundaries at high pressure altitude. Yaw damper inoperative speed (minimum): Above 20,000 ft. Initially known as. 3 VSO KCAS (max gross weight)). A Dart library to perform standard and non-standard atmosphere property calculations and speed conversions. 78. G. Do not exceed this speed with flaps down. The Tiger cruises at 160 mph, with a 170 mph top speed. For a more accurate answer please select 'decimal' from the options above the result. Consider KTAS as the speed a plane would be going on the ground, while IAS offers a more accurate measurement in the air. For 15,000 feet max AB, your best performance is between 400-450 KCAS (0. 150 KTS . Study with Quizlet and memorize flashcards containing terms like Gross weight with fuel and 2 souls, One engine thrust MIL, One engine thrust MAX and more. What is the relationship between induced and parasite drag when the gross weight is increased?Find the Calibrated Lift-Off Speed [KCAS]. 91 * 50 is 45. Maneuvering speed (V A) at this weight is about 122 kcas. Vstall is measured as a true airspeed, it increases approximately 1% for every thousand feet increase in altitude. S. An airplane’s maximum operating limit speed. 7 degrees per 0. A kilometer per hour is a unit of speed. To determine this value we consider the following variables: Note that neither the mass nor the weight of the aircraft is included. KTAS is the acronym for true airspeed of an airplane charter measured in knots. 88 IMN and it drops off sharply at about 0. Conversion of true airspeed to the equivalent airspeed can be done directly by: VEAS = V ⋅ √ ρ ρ0. Your airspeed indicator (assuming no errors) will read only 68. Abbreviation is mostly used in categories: Aviation Military Government Army Ministry Of Defense. Vfe. 6) MINIMUM CONTROL SPEEDS NOTE: The airspeed limitations apply to all masses (weights) up to 65,200 lb (29,574 kg) gross weight, unless otherwise stated. 2 KCAS, a 12% reduction in the stall speed. 5 KCAS AOCmax Best angle of climb 3. However, we have based our knots calculator on the international nautical mile which is commonly used thoughout the world today. b) The airspeed indicator and the altimeter. Likewise, Daniel and Bonnie Williams, owners of a 1994 114B, flight plan about 150 KTAS on 65-percent power and about 12 gph. 200 knots. Maximum number of passengers on board: The actual number of passengers - excluding infants - shall not exceed the number of serviceable seats provided with seat belts and the number of life vests - when required under CFR 121.