QNH is the atm pressure at S.L. (Question Nil Height - what is the atm pressure at nil height i.e. sea level)
1) Set QNH as the reference pressure - altimeter reads height above sea level. E.g. QNH of the day is 1022. We set 1022 in the subscale then the altimeter will read the height of the aircraft above the sea. This is called ALTITUDE.
QFE is the atm pressure at a particular field. FE is Field Elevation.
2) Set QFE then the altimeter will read the height above the field. How do we do that? If the hands of the altimeter are forced to read ZERO while the aeroplane is on the ground the reference pressure will be QFE and the altimeter will read height above the field. This is zero as the a/c is on the ground.
3) If the QNH is again set while the a/c is on the ground at this field the altimeter will once again read the height above the sea. In this case it is called ELEVATION.
- 5 m from sealed building
- 6 m from a/c
- 15 m from exposed public area
- unsealed building - 15m if MTOW more than 5700 Kg, 9m if less than 5700 Kg
2. If fuelling equipment is mobile, then it shall be so placed that it can be moved rapidly in the event of a fire. If the fuelling equipment is NOT mobile then the a/c shall be placed that it can be moved away rapidly.
3. No persons on board allowed during fuelling.
4. All engines stop and ignition switches in the "OFF" position.
5. No maintenance work done to the radar, radio, electrical and electronic systems.
6. The a/c and fuelling equipment must be connected to the same electrical potential. If an earth point is available then the a/c and fuelling equipment are connected to it.
7. Footwear worn must be of non-sparking type. No matches, cigarette lighters carried.
8. No smoking or naked fire within 15m.
9. At least 2 fire extinguishers must be positioned between 6m to 15m of the a/c and fuelling equipment or carried on the fuelling equipment.
SEAT BELTS CAO 20.16.3
1. Each crew and each passenger should wear a safety harness or seat belt during take off and landing, in turbulent conditions and when the a/c is flying at a height less than 1000 Ft above the terrain and during an instrument approach.
CARGO CAO 20.16.2
1. All cargo stowed shall be restrained to prevent any article from moving under the max accelerations to be expected in flight, in a heavy landing and in a ground loop.
2. Cargo cannot be carried in any place where it may damage, obstruct or cause failure of flight controls, electrical wiring, pipe lines, and essential a/c equipment.
3. Cargo may be carried on a pax seat if the weight is evenly distributed and is less than 77 Kg.
4. Cargo may be carried on an unoccupied control seat if the MTOW is less than 5700 Kg, it weighs less than 77 Kg, and the cargo or means of restraint does not interfere with flight controls.
- aerial spotting, no remuneration by pilot or a/c owner or person/organisation on whose behalf the spotting is conducted
- AG operations on land owned and occupied by a/c owner
- carriage of persons/goods (pilot or a/c owners property) with no charge
- conversion training for the purpose of endorsement of an additional type or category of a/c in a pilot licence
- cost sharing of a flight where all persons share equally the costs of the flight, and no payment is made for the crew's services. No public notice of the flight has been given and max number of persons on the flight including the crew is 6.
COMMERCIAL CAR 206
Aerial work:
- aerial survey
- aerial spotting
- ag operations
- aerial photography
- flying training other than conversion training (i.e. that is private operation because the person undergoing the training is already a holder of a pilot licence)
**CONVERSION TRAINING FOR THE PURPOSE OF ENDORSEMENT OF AN ADDITIONAL TYPE OR CAT. OF A/C IN A PILOT LICENCE IS A PVTE OPERATION**
- air ambulance
- carriage for the purpose of trade of goods being the property of the pilot, a/c owner or hirer of the a/c (but NOT with fixed schedules to and from fixed terminals)
In short flights conducted for the purpose of making money but do not involve members of the general public. The flight is considered commercial if ANYONE gets paid e.g. an aerial advertising flight is still aerial work even if the pilot does not get paid.
CHARTER:
- The carriage of persons or goods for hire or reward other than with a fixed schedule to and from fixed terminals. Unlike aerial work, CHTR does involve the general public but the pilot cannot fly a time table. A CHTR operator cannot offer the public a time table, he can only respond to demand.
- The carriage of persons or goods, in accordance with fixed schedules to and from fixed terminals, in circumstances in which the accommodation in the a/c is not available for use by persons generally.
A charter operator can fly a regular route at regular times but only at the request OF A PARTICULAR customer. So not carry persons generally.
RPT
- fixed schedules to and from fixed terminals over specific routes
4) Knew requirements for an AOC
CONDITIONS ON AIR OPERATOR'S CERTIFICATE (AOC) AUTHORISING CHTR OPS & AWK OPS ( CAO 82.1)
1. ORGANIZATION & FACILITIES
- sufficient qualified personnel to operate services provided
- establish a Chief Pilot position and appoint a person in that position
- more supervisory position may be required by CASA
- sufficient facilities and documentation
- Operations Manual (Ops Man)
- copies of Ops Man given to crew members
2. TRAINING & CHECKING - flight crew requirements
- ensure PIC of multi engine a/c (not exceeding 5700kg MTOW) in a VFR CHTR op has at least 100 hours command and at least 5 hours as PIC for the a/c type.
- 10 hours PIC of the type if IFR CHTR op.
3. OPERATING DIFFERENT AIRCRAFT MODELS
- ensure Ops Man current and appropriate info to operate the a/c in accordance with the specific instructions for the a/c type and models.
- Chief Pilot must be satisfied that a pilot is competent to operate the a/c in accordance to the specific instructions.
- understand the differences in each model of the type.
- the Ops Man, the Maintenance Control Manual contain appropriate maint. control instructions.
- a current POH or Aircraft Flight Manual attached to the Ops Man contain the specific instructions.
4. OBLIGATION TO COMPLETE AOC HOLDERS SAFETY QUESTIONNAIRE within time if given by CASA
APPENDIX 1:
Facilities and Documentation.
1. Facilities
- has an operating HQ for CASA communications
- Buildings of adequate sizes and suitable for the operations.
2. Documentation
- reference library - Operational doc including CAA, CAR, CAO applicable to the operations.
- AIP relevant to the class of ops.
- Ops Man
- Dangerous goods manual
- Maintain distribution list of operational doc to staff.
- Record of flight crew recent experience status, licence currency, ratings & endorsements
- Record of flight time and duty time
- Training file of flight crew: ground training, endorsement training, flight or sim proficiency checks.
- Pax list
- Fuel instructions and records
- A catalog of authorized landing areas where the ops are frequently conducted.
APPENDIX 2
TRAINING & CHECKING ORGANIZATION (TCO)
Management:
- Chief Pilot is responsible for the effective management of the TCO.
- sufficient personnel to conduct training, examinations and proficiency checks.
GROUND FACILITIES, EQUIPMENT & TRAINING AIDS
- sufficient facilities provided.
- library of training reference publications & operational documentation
- flight sims and or synthetic trainers may be used. Maintained and operated according to Manual of Standards (MOS).
- able to train proficiency in emergency procedures.
TRAINING AND CHECKING MANUAL
- TCM must be provided and conveniently accessible by flight crew.
Structure of TCO:
- duties and responsibilities of T&C staff.
- recent experience & proficiency requirements of T&C staff.
- course outlines, syllabuses and accomplishment standards
- command responsibility requirements for the conduct of flight proficiency checks.
- procedures of simulated emergency and abnormal flight ops.
- admin requirements e.g. doc, records, certificates.
- security arrangements for exam materials.
- process to be followed when a satisfactory standard is not achieved.
5) Knew type of information contained in Ops Manual
Ops Man contains information relevant to the classification of ops for the organisation.
-Operational information such as common airfield data, types of licences offered, qualifications of PPL, CPL, aircraft loading sheets
6) Knew requirements relating to drug and alcohol requirements (CAR 256)
- a person shall not, while in a state of intoxication, enter any aircraft.
- a crew member shall not consume any alcoholic liquor, drug, pharmaceutical or medicinal preparations or other substance that may impair his capacity to act as a crew member.
- no alcoholic liquor to be consumed at least 8 hours before departure of the aircraft.
- while on board an aircraft as a crew, no alcoholic liquor is to be consumed (total abstinence).
Long term effects of alcohol:
- short term effects are "hangover" effects of nausea, headache, gastritis and thirst.
- frequent indulgence may cause cancer of the mouth, oesophagus and stomach, damage to the heart and liver.
Effects of prescription or OTC drugs:
- can affect human performance. Drowsiness and dizziness are common side effects. Be sure to advise your GP is he is not a DAME that you fly before accepting the prescription drug for a treatment.
ANALGESICS - Pain relievers. May be used by pilots for the treatment of short term pain such as headaches and muscle pain.
Aspirin (Aspro/Disprin) - can cause stomach upsets, internal bleeding and kidney problems.
Codein (Panadein) - can be additive and cause constipation.
Paracetamol (Panadol/Dymadon) - taken in excess, can damage liver and kidneys.
ANTIHISTAMINES - used to clear up congestion associated with colds, flu and sinus. side effects are drowsiness and degraded performance. NOT to be taken when flying!
EPHEDRINE - often found in nasal sprays.
STIMULANTS (AMPHETAMINES & CAFFEINE) - amphetamines are illegal, causes short-tempered restlessness, disorientation, fits of anxiety, overconfidence and headaches.
caffeine - too much cause sleeplessness and irregular heat rhythms. Habitual.
ANTIBIOTICS - normally no detrimental effect on a pilot's ability to fly. Some pilots may have an allergic reaction to some antibiotics.
- side effects include diarrhoea.
- since antibiotic is prescribed to treat some infection and so best not to fly.
TRANQUILLISERS - treat anxiety or tension, should never be used without medical consultation.
- side effects include drowsiness, dizziness and increased susceptivity to alcohol.
SEDATIVES - treat sleep disorders, should never be used without medical consultation.
- side effects include dizziness, blurred vision, headaches and skin irritations. Habitual.
BLOOD PRESSURE MEDICATION - high or low blood pressure can be a reason for flying disqualification.
- some drugs may be acceptable for pilots. Check with DAME.
Effects of illicit drugs:
- can affect profoundly human mood and performance. Can be broadly compared to the effects of alcohol.
- unsealed building - 15m if MTOW more than 5700 Kg, 9m if less than 5700 Kg
2. If fuelling equipment is mobile, then it shall be so placed that it can be moved rapidly in the event of a fire. If the fuelling equipment is NOT mobile then the a/c shall be placed that it can be moved away rapidly.
3. No persons on board allowed during fuelling.
4. All engines stop and ignition switches in the "OFF" position.
5. No maintenance work done to the radar, radio, electrical and electronic systems.
6. The a/c and fuelling equipment must be connected to the same electrical potential. If an earth point is available then the a/c and fuelling equipment are connected to it.
7. Footwear worn must be of non-sparking type. No matches, cigarette lighters carried.
8. No smoking or naked fire within 15m.
9. At least 2 fire extinguishers must be positioned between 6m to 15m of the a/c and fuelling equipment or carried on the fuelling equipment.
SEAT BELTS CAO 20.16.3
1. Each crew and each passenger should wear a safety harness or seat belt during take off and landing, in turbulent conditions and when the a/c is flying at a height less than 1000 Ft above the terrain and during an instrument approach.
CARGO CAO 20.16.2
1. All cargo stowed shall be restrained to prevent any article from moving under the max accelerations to be expected in flight, in a heavy landing and in a ground loop.
2. Cargo cannot be carried in any place where it may damage, obstruct or cause failure of flight controls, electrical wiring, pipe lines, and essential a/c equipment.
3. Cargo may be carried on a pax seat if the weight is evenly distributed and is less than 77 Kg.
4. Cargo may be carried on an unoccupied control seat if the MTOW is less than 5700 Kg, it weighs less than 77 Kg, and the cargo or means of restraint does not interfere with flight controls.
8) Knew VFR Day charter instrument requirements
CAO 20.18 Appendix 1 - VFR Minimum Flight Equipment for a/c below 5700 Kg
1. ASI
2. ALTIMETER
3. COMPASS
4. A TIMEPIECE with hour, minute and second hand. This may be a watch worn by the pilot or navigator
In addition for an AWK or CHTR VFR flight, must have:-
5. TURN/SLIP INDICATOR
6. AN O.A.T. INDICATOR when operating from an aerodrome at which ambient air temp is not available from ground-based instruments.
Requirement for VHF radio (AIP GEN Para 1.1):-
For VFR:
1. When in CTA in Class A, C, D or E.
2. When OCTA (Class G) but above 5,000 ft AMSL
3. When OCTA below 3,000 ft AMSL or 1,000 ft AGL in reduced VMC
4. When in the vicinity (10NM) of a CTAF(R) Aerodrome.
* reduced VMC means clear of clouds and visibility up to 5,000M.
** IFR, NVFR & CHTR - must be fitted with VHF radio in A, C, D, E & G
*** No need VHF radio if not flying in CTA and CTAF (R), below 5,000 ft AMSL in Class G, not in reduced VMC i.e. 1500ft horizontally and 1000ft vertically from cloud and visi more than 5,000M.
Requirement for HF radio (AIP GEN Para 1.1):-
VFR/IFR must be fitted with HF in A, C, D, E, G & Remote Area if NO ELB/ELT is fitted.
* IFR & CHTR - must be fitted with HF radio when VHF does not allow continuous comm with ATS at ALL stages of flight.
Requirement for ELT or ELB to be carried:-
(CAR 252A)
All Australian aircraft must be fitted with an approved ELT/ELB unless:-
1. Less than 50 NM from an aerodrome (provided a/c is fitted with HF radio)
2. Agricultural ops
3. CASA has given permission
4. New a/c and the flight is a test flight or ferry flight
5. In process of flying the a/c to a place to have ELT/ELB fitted or to have the fitted ELT/ELB repaired/overhauled
6. Temporarily removal for inspection, repair, mod, or replacement; and an entry has been made in the log book stating the make, model and s/n, and the date of removal and the reason for removal. In addition, a placard stating "ELT not installed or carried" in the a/c that can be seen by the pilot; and that not more than 90 days since the removal.
9) Knew privileges and limitations of CP(A)L
Qualifications of a CP(A)L CAR 5.104 5.09 (1)
Sufficient English proficiency
Qualified to hold the licence
Fit and proper person
- at least 18 years old
- holds a radiotelephone operator licence
- awarded a pass in CP(A)L theory exam
- awarded a pass in CP(A)L flight test
- meets standards set out in aeroplane syllabus
- meets aeronautical experience requirements in CAR 5.111 (150 hours etc)
Authorization CAR 5.105 (PRIVILEGES) – when endorsed and rated
- able to fly a single pilot aeroplane as PIC while engaging in any operation
- able to fly a multi-pilot plane as PIC. While engaging in any operation other than a CHTR or RPT
- able to fly as a co-pilot in any operation
Regular flight review requirement for a CP(A)L CAR 5.108 (AFR LIMITATIONS)
- satisfactorily completed an aeroplane review once every 2 years
Recent experience requirements CAR 5.109 (RECENCY LIMITATIONS)
- must not fly as PIC. if carrying any other person if he has not, within 90 days before the flight, carried out 3 take-offs and 3 landings while flying as PIC or in dual flying (day) or
- within 90 days before the flight, carried out 3 take-offs and 3 landings as PIC or in dual flying (night)
CAR 5.110 (AGE LIMITATIONS)
CP(A)L must not fly as a PIC. if over 60 years old if engaged in commercial operations and that is carrying passengers. Can fly as PIC. if a/c is fitted with dual controls and an operating crew that includes a qualified pilot (commercial or ATPL) who is not the PIC.
- If less than 65 years old - annual aeroplane flight review required.
- If at least 65 years old - 6 monthly aeroplane flight review.
10) Knew single pilot VFR flight & duty time
Flight and Duty Time Limits - extract/apply the rules pertaining to flight and duty time limitations.
Commercial pilots are subject to flight time and tour of duty limitations as per CAO48. Para 1.4 says that notwithstanding what rest or duty pattern may apply it is still an offence to fly if any physical (illness) or mental condition (fatigue) is likely to impair our performance and safety is impaired.
FLIGHT TIME - total time from when the a/c moves under its own power for the purpose of taking off until when it comes to rest at the end of the flight
RESERVE TIME - period during which the crew is required to hold himself available for a tour of duty (i.e. standby time).
REST PERIOD - period during which the crew is relieved of all duties associated with his employment.
TOUR OF DUTY - period between when crew commences any duties prior tomaking a flight or a series of flights until he is finally relieved of all such duties after the termination of such flight or series of flights and includes reserve time at the airport.
(If you turn up for work and due to an unserviceable airplane or weather you do not make the flight, you have not done a tour of duty even if you stay at work and clean the hangar! If you are a flight instructor and you turn up on a wet day and you cannot not fly, you have not done a tour of duty even if you stay at work and teach ground school! However you would have done "duty time". Duty time includes tour of duty and any other non-flying duties associated with your employment. Limit on duty time is 90 hours every fortnight. CAO 48.1.1.13)
WAITING TIME - all the time spent during a tour of duty of any nature associated with the tour 1) prior to departure (e.g. flight planning), 2) on the ground at intermediate stopping places (e.g. refueling) and 3) after arrival (e.g. post flight briefing, refueling) at the destination airport.
CONDITION 1:
(CAO 48.1.1.2)
Before embarking on a tour of duty or reserve time a crew must have:-
A Minimum Rest Period of (a) 9 consecutive hours between 10pm and 6am local time OR (b) if outside of this range of time, 10 consecutive hours.
CONDITION 2:
(CAO 48.1.1.13)
Duty time limit of 90 hours a fortnight.
CONDITION 3:
(CAO 48.1.1.3)
Tour of duty limit of a maximum of 11 hours.
CONDITION 4:
(CAO 48.1.1.4)
A maximum of 8 hours flight time in any one tout of duty.
CONDITION 5: EXTENSIONS OF TOUR OF DUTY AND FLIGHT TIME BEYOND 11 HOURS
(CAO 48.1.1.5 and 1.6)
- A tour of duty may be extended to 12 hours (from 11 hours).
- A flight time may be extended to 9 hours (from 8 hours).
CAO 48.1.1.7 But then the crew must have:
a rest period of 1 additional hour for every 15 minutes or part thereof extension of the tour of duty.
Example if the tour of duty is 11 hours and 50 minutes then the rest period will be:-
If between 10pm and 6am then rest period will be 9 hours + 4xhours = 13 hours; and if outside of the 10pm to 6am range, then 10 hours + 4 hours = 14 hours.
NOTE: The tour of duty and flight time extensions are NOT cumulative i.e. If your tour of duty is extended to 11 hours 50 minutes and the flight time is extended to 8 hours 50 minutes there will be ONE LOT of extended rest period of 13 hours/14 hours only.
CAO 48.1.1.9 If tour of duty exceeds 12 hours or the flight time exceeds 9 hours then the rest period is 24 consecutive hours.
EXCEPTION to the 11 hour rule is 1.17 an AWK or CHTR pilot may in VFR only perform more than 11 hours tour of duty but not more than 15 hours subject to:
(a) Not less than 4 consecutive hours of rest where the pilot if free of all duties associated with work; within the tour of duty.
(b) A rest period of at least 24 hours between 2 consecutive tours of duty each more than 11 hours.
(c) No more than 2 tours of duty of 11 hours or more each within 6 consecutive days.
(d) No more than 6 hours of flight instruction on any tour of duty which is in excess of 11 hours.
CONDITION 6:
(CAO 48.1.1.10)
2 Consecutive tours of duty
If you have done 2 consecutive tours of duty with the minimum rest period in between and if the SUM of the 2 tours exceed 11 hours or 8 hours of flight time then your next rest must be at least 12 hours including the hours of 10pm to 6am; or 24 hours if not embracing the hours between 10pm to 6am.
FURTHER LIMITS ON FLYING HOURS:-
You cannot fly more than 8 hours in one tour of duty (tour of duty limit 11 hours)
You cannot fly more than 30 hours in one week (7 days)
You cannot fly more than 100 hours in one month (30 days)
You cannot fly more than 900 hours in one year (365 days)
Duty Hour Limit:
You cannot work more than 90 hours of duty time in each fortnight.
11) Knew CP(A)L Maintenance Authorizations:
CAAP 43-1(0) relates to the preferred procedures relating to MR and CAR 43
- an aircraft must not fly unless there is in force a valid MR covering the period of the proposed flight.
Part 1 of MR: (Refer Bob Tait)
1. check a/c rego VH-
2. Check the current date is NOT later than the expiry date of MR or that the current TTIS (time in service) does not exceed the expiry hours.
3. The organization and approved person issuing the MR
4. whether the a/c is for IFR, VFR DAY OR VFR NIGHT
5. Operation category i.e. PVTE, AWK, CHTR or RPT
6. check that the current date or TIS does not exceed the date or TIS of any maintenance item due unless it has been signed off by a qualified person.
Part 2 of MR: (DAILY INSPECTION)
- PIC must sign for satisfactory completion of daily inspection
- at completion of each day's flying (last flight) PIC. or other approved person must record on MR the total FLIGHT TIME for the day in the Progressive A/C TIS columns.
Part 3 of MR: (RECORD OF DEFECTS AS ENDORSEMENTS)
- record defects as ENDORSEMENTS. a/c must not be flown until the endorsement is signed off by a suitably qualified person CAAP 43-1 (0) PARA 5.1
**REVIEW SCHED 5 CASA MAINTENANCE SCHEDULE daily inspection Bob Tait's page 2.42 and 2.43
**REVIEW SCHED 8 MAINTENANCE THAT MAY BE CARRIED OUT ON A CLASS B A/C BY A PILOT (CAR 42 ZC (4) (D)) bob Tait's pages 2.44 and 2.45
2) You may navigate by the use of RADIO NAVIGATION AIDS
Navigating by visual reference you must:-
- Remain in VMC
- Obtain a positive fix at least every 30 minutes
- Within CTA advise ATC if you discover that the a/c had diverged more than 1 NM from the track given in your airways clearance.
Navigating by Radio Navigation Aids you must have one of the following qualifications:-
- Hold an IR endorsed on the aid/aids
- Hold a Night VFR Rating endorsed on the aid/aids
- Hold at least a PPL and have been instructed by a qualified flight instructor in the use of the aid/aids as the sole means of navigation and you have been assessed as competent to use those aids.
You must:-
- Remain VMC
- Use an approved GPS
- After allowing for 9 deg Track Error either side of FPT, come within the rated coverage of a navigation aid which can be used to fix your position, and you obtain a positive fix at least every two hours.
- When flying at or above BKN clouds consult forecast to ensure VMC can be maintained during the climb, cruise and descent.
- A/c's equipment as per Night VFR CAO 20.18 Appendix IV
- In CTA advise ATC if off track by more than 5 deg from assigned track given in your airways.
When tracking via a VOR, 5 deg is half scale deflection of the CDI. In the unlikely event that you are tracking via a localizer you must also advise ATC if you have diverged more than half scale deflection on the localizer.
AIP ENR 1.1 Para 17.4.6 describes the approved methods of obtaining a fix based on radio navigation aids. They are:-
1) The intersection of 2 or more radio position lines at an angle not less than 45 deg
2) The passage of the a/c over the NDB, VOR or DME station (Station Passage)
If the aids are NDBs - if a positive fix is based on the intersection of 2 position lines from NDB alone, then both NDBs must be within 30 miles of the aircraft no matter what their rated coverage might be.
DEAD RECKONING
DR = IF YOU HOLD A CONSTANT HEADING, HEIGHT & POWER SETTING (TAS) IN A CONSTANT WIND, THE PATH YOU FLY ACROSS THE MAP WILL BE CLOSE ENOUGH TO A STRAIGHT LINE.
Hence the GS will also be constant and we can work out the time to fly a particular distance.
S = D/T Therefore, T = D/S where S = GS
The method of following DR:
1)LOOK AT THE MAP FIRST
-ESTABLISH A DR POSITION (what is the distance travelled) from the last POSITIVE fix.
-REFER TO CLOCK (how much time has elapsed since the positive fix).
-WHAT IS THE GS? (Obtain from GPS or S = D/T formula).
-LOCATE THIS DR POSITION ON THE MAP.
-NOTE THE MAIN/MAJOR FEATURES ON THE MAP relating to this DR position.
-DON’T LOOK OUT THE WINDOW until you have the features you expect to see!
2)THEN LOOK AT THE GROUND
-REFER FROM MAP to the Ground.
-LOOK FOR THE FEATURES you have found on the map
-FIND BIG FEATURES FIRST then look for more details.
-FIND A COMBINATION of details & features to CONFIRM your position.
-DO NOT JUMP TO CONCLUSION WHERE YOU ARE!!!
-THE WIND may have blown you off course!!!
SUMMARY OF Critical Performance Data:-
Theoretical & The Practical (Easier to remember)
Vx 77 Kts
Vy 87 Kts..... V Climb 90 Kts (Best Rate Of Climb)
V cruise climb 104 Kts
Vr 65 - 75 Kts (V Rotate 70 Kts)
V toss 72 Kts
Vgup 108 Kts ..... V U/C retract BEFORE reaching 109 Kts
Vlo 130 Kts ..... Gear Extension Speed. Do not exceed 130 Kts Before extending the U/C
Vle 130 Kts ..... Gear Extended Speed. Do not exceed 130 Kts with U/C extended
All performance data for a/c is given in relation to the standard atmosphere. We must be able to convert ambient conditions prevailing at a particular aerodrome to an equivalent height in ISA.
Pressure Ht= Ht in the standard atmosphere where the pressure is the same as the sample of air being considered. (It is a measure of PRESSURE, not Height!)
At a lower QNH the field elevation must be higher than Sea Level as the air density is lower.
Example:-
Field elevation of an aerodrome is 1500 Ft. Atm pressure at S.L. on that day is 1000 hPa. At what level in the std atm would the air be the same pressure as the air in the field?
We are asked to find the PRESSURE HEIGHT of the field.
Want to know the height of the field, not above the sea (on that day the QNH is 1000 hPa), but above the 1013 hPa pressure level which is the starting point for the std atm.
1013 is greater than the QNH of the day, 1000 hPa; therefore it must be further down than S.L. since pressure in the atm can only increase with decreased ht (1013 is > 1000).
1013 must be (1013-1000)=13 x 30 Ft = 390 Ft below the sea on that day.
Hence the ht of the field above the 1013 pressure level is 1500+390=1890 Ft. This is the Press Ht. of the field. The airplane will behave and perform according to the 1890 Ft figures and not the 1500 figures.
PRESSURE HT = ELEVATION + (1013-QNH) X 30 PRESSURE HT INDICATES THE HEIGHT IN THE STANDARD ATMOSPHERE WHERE THE PRESSURE IS THE SAME AS THAT AT THE LOCATION BEING CONSIDERED.
Density Height
is the height in the std atm (ISA) where the air has the same density as the sample of air being considered. (It is a measure of density, not height!)
Press Ht concerns with air density changes due to atm pressure. We need to consider air density changes due to temp also.
ISA Temp - What is the behavior of temp in the std atm? SL std temp is 15 C. As temp drops at a std rate of 2 C per 1000' of height increase we can then calculate the std temp in ISA at any level.
E.g. at 4,000 Ft in the std atm the temp must be 15 - 2 x 4 = 15 - 8 = 7 C
This is called ISA Temp.
Temp Deviation - As air temp increases, air density decreases. Since density also decreases with increased ht, increases in air temp have a similar effect on density as an increase in ht ie an a/c will perform on a HOT day as though it is operated at a higher level in the std atm. Conversely it will operate on a cold day as though it is at a lower level.
Each deg C of temp rise = density decrease equiv to a ht increase of 120 Ft
E.g. on a hot day when the temp is 10 C hotter than ISA the a/c feels like it is operating at 10 x 120' = 1200 Ft higher.
Each deg C of temp drop = density increase equiv to a ht decrease of 120 Ft.
To calculate Density Ht we need pressure (i.e. Pressure Ht) and temp deviation from std atm:-
Example:
Find the density ht of an aerodrome which has an elevation of 2100 Ft if the QNH is 1000 hPa and the temp at the field at the time is +25C.
1) Given elevation and QNH we can find Pressure Height.
1013-1000=13
13 x 30 = 390 Ft
Press Ht is then 2100 + 390 = 2490 Ft
2) Temp drops at a std rate of 2 C per 1000 Ft rise.
Use Press Ht of approximately 2500 rounded off to nearest 500 Ft. So temp at a pressure ht of 2500 Ft must be colder than ISA:
ISA temp is 15 - (2 x 2.5) = +10C
Actual temp at the field is 25 C, therefore ISA Temp is COLDER than OAT hence PLUS.
ISA deviation is PLUS 25-10=+15 C
3) Multiply ISA deviation by 120 to obtain the correction that must be applied to the Pressure Ht to allow for the non std temp.
