Home |
Why AWOS? |
Service to Pilots |
Meets
All Requirements |
Affordable By Any Airport |
Easy to Buy | 'How To' Information & Videos |
Maintenance & Support |
FAA Certifications |
References | ||
|
Easy to Install | Easy to Maintain |
FAA FLIGHT REQUIREMENTS | Traditional AWOS | SuperAWOS |
SUPERAWOS CERTIFICATION |
||
IFR Instrument Flight Rules |
Commercial Flight Ops (Part 135++) |
ALTIMETER
&
VISIBILITY Ceiling Not Required - Since 1966! |
|||
Private Flight Ops (Part 91) | ALTIMETER | ||||
VFR Visual Flight Rules |
Private & Commercial (Part 91 & 135) | PILOT'S DISCRETION | |||
"Visibility is the sole criterion to initiate an instrument approach" |
click paragraph for PDF of entire letter |
||||
Helicopter Emergency Service
Even without any |
|
||||
IFR ALTERNATE AIRPORT |
Forecast
of Conditions Meets Alternate Airport Requirements
An AREA forecast may be used |
CEILING NOT REQUIRED! |
QUESTION: Does a Part 135 operator need weather reporting to determine if a flight is VFR? D. Part 135. Whenever a part 135 operator is required to use a weather report or forecast for IFR operations, the operator must use weather reports or forecasts prepared by the NWS, or a source approved by the NWS. Where NWS services are not available, the source must be approved by the FAA. If NWS or other approved reports are not available for VFR operations, a pilot in command (PIC) may use weather information based on his own observations or on those of other competent persons. For this purpose, the FAA considers certificated commercial pilots, airline transport pilots, dispatchers, air traffic controllers, and trained weather observers competent to provide weather information for part 135 VFR operations. Source: http://fsims.faa.gov/PICDetail.aspx?docId=EE2EBFD3E81834CB8525734F007665BC =========== QUESTION: Is a ceiling required for a Part 135 operator to take off? 2) Approval of non-federally owned and operated AWOS. a) Automated systems installed and operated as independent systems under the guidelines of AC 91‑54 are not approvable for part 121 and part 135 operations. This type of system may be used only as a basic source of weather data for a SAWRS. b) AWOS-1 installed, operated, and maintained under the guidelines and specifications in AC 150/5220-16 or part 171 subpart K are not approvable for part 121 /135 operations when operated as an independent system. This type of system may be used as a basic source of weather data for a SAWRS. c) AWOS-2 that meet the criteria of AC 150/5220-16 or part 171 subpart K are approved for part 121 and part 135 operations with the following limitations:· An IFR operation which requires ceiling information as a condition for conducting that operation is not permitted at airports where AWOS-2 reports are the official source of weather information,· AWOS-2 airports cannot be used for alternate airports based solely on AWOS-2 reports (no cloud height information),· AWOS-2 reports may not be used as the sole basis for determining if VFR conditions exist at airports without operational control zones,· POIs must examine each request for approval for AWOS-2 operations and are authorized to impose any additional limitations determined necessary, and· At airports where ceiling information is required to comply with nonstandard takeoff minimums dictated by part 97 or OpSpecs, IFR takeoffs are prohibited if an AWOS-2 is the sole source of weather information. Note: At airports where a climb gradient alternative is specified, however, this restriction would not apply to aircraft capable of meeting climb gradient criteria. source FAA FSIMS: http://fsims.faa.gov/PICDetail.aspx?docId=EE2EBFD3E81834CB8525734F007665BC
|
|
1.
FAA - AIRMEN INFORMATION MANUAL |
|
"...the rule requires a forecast
of a specific ceiling and visibility for an airport to be used as an
alternate, under 91, 135 or 121.
Note: This [requirement] is for use as an alternate, not to meet the requirements to begin an approach.
"An AWOS-AV (altimeter and visibility) satisfies the information
required to begin an approach under 135."
Manager, Commuter, On Demand and Training Center Branch, AFS-250
10-23-06 |
3. FAA OPERATIONS SPECIFICATION Ceiling Not Required for Any flight operations
FAA has a new system called FSIMS It makes excellent nighttime reading. This is a GREAT site - Hooray FAA! |
OPSPEC C064, TERMINAL AREA IFR OPERATIONS IN CLASS G AIRSPACE AND AT AIRPORTS WITHOUT AN OPERATING CONTROL TOWER—NONSCHEDULED PASSENGER AND ALL-CARGO OPERATIONS. C064 authorizes an operator to conduct nonscheduled passenger and all-cargo (scheduled and nonscheduled) terminal area IFR operations in Class G airspace or into airports without an operating control tower, with the following limitations and provisions:A. Before authorizing C064, the POI must determine that the operator has a method or procedure for obtaining and disseminating necessary operational information. This operational information must include the following:1) The airport is served by an authorized IAP (and departure procedure when applicable);2) Applicable charts for crewmember use;3) Operational weather data from an approved source for control of flight movements and crewmember use;4) Status of airport services and facilities at the time of the operation; and5) Suitable means for pilots to obtain traffic advisories.6) Sources of Traffic and Airport Advisories.B. Certificate holders may be authorized to use any two-way radio source of air traffic advisory information listed in the AIM (for operations in U.S. airspace) or equivalent Aeronautical Information Publications (AIP) (for foreign operations).1) These sources include common traffic advisory frequencies, UNICOM, MULTICOM, and flight service stations.2) In those cases where two sources are listed at the same airport, inspectors must ensure the operator’s manuals have procedures which require pilots to continuously monitor and use the traffic advisory frequency when operating within 10 NM of the airport. The procedures should require communication concerning airport services and facilities to be completed while more than 10 miles from the airport.3) At some airports no public use frequencies may be available. In those cases, a certificate holder must arrange for radio communication of essential information including surveillance of local or transient aircraft operations by ground personnel. Ground personnel who operate a company radio for airport status and traffic advisory must be able to view airspace around the airport.C. OpSpecs C064 and/or C080 may need to be issued to the certificate holder in order for the OpSpec C081, Special Non 14 CFR Part 97 Instrument Approach or Departure Procedures, to be issued which authorizes the use of special (non-part 97)) instrument approach or departure procedures.D. C064 is applicable to part 121, 125, 121/135, and 135 certificate holders. For helicopter authorization, see OpSpec H121. Part 91 subpart K program managers should use MSpec A014 for Class G operations.
|
|||
4-147 EVOLUTION OF ALL WEATHER TERMINAL OPERATIONS (link to FAA's new FSIMS tools!) "When turbojets were introduced (1950s), the concept of operating minimums was based on ceiling and visibility" "The basic turbojet minimums are currently specified as a decision height (DH) of 200 ft. and a visibility of 3/4 statute miles (RVR 4000)." "These changes were finalized by the publication of U.S. TERPS criteria in 1966. This conceptual change eliminated the ceiling requirement by introducing a decision height (DH) and based landing minimums on runway visual range (RVR) reports, when available, instead of ground or flight visibility reports." "This conceptual change was necessary because of the limitations in the methods used to observe or measure ceiling and visibility (see section 2, paragraph 495). Often ceiling and visibility observations were taken several miles from the approach end of a runway, and as a result were frequently not representative of the seeing-conditions encountered during the final stages of an approach and landing, especially in rapidly changing or marginal weather conditions." FAA HQ FLIGHT STANDARDS: "If the approach minimums require one mile, and a 135
pilot HAS the required visibility, even if they were given a report of 100 foot ceilings, they are
authorized to shoot the approach to decision height." |
||||
4.
CEILING NOT VERY ACCURATE
Imposes High Annual Costs |
||||
|
5. INSTRUMENT
APPROACH PLATES
First, let's
clear up the bit of confusion about those often misunderstood numbers on
approach plates: There ARE NO CEILING minimums for civil aircraft,
anywhere on an approach plate.
"MINIMUMS IN PARENTHESES NOT APPLICABLE TO CIVIL PILOTS"
"MINIMUMS IN PARENTHESES NOT APPLICABLE TO CIVIL PILOTS"
6. APPLICABLE WEATHER MINIMUMS
FAA PART 97 STANDARD INSTRUMENT APPROACH PROCEDURES
(a) A means alternate airport weather minimum.
(s) S means straight-in landing minimum, a statement of ceiling and visibility, minimum descent altitude and visibility, or decision height and visibility, required for a straight-in landing on a specified runway. The number appearing with the S indicates the runway to which the minimum applies. If a straight-in minimum is not prescribed in the procedure, the circling minimum specified applies to a straight-in landing.
(v) T means takeoff minimum.
(x) Visibility minimum means the minimum visibility specified for approach, or landing, or takeoff, expressed in statute miles, or in feet where RVR is reported.
(e) Ceiling minimum means the minimum ceiling, expressed in feet above the surface of the airport, required for takeoff* or required for designating an airport as an alternate airport.
FAA Part |
Takeoff Minimums | Alternate (airport) Minimums |
91 |
P§ 91.175 Takeoff and landing under IFR. For all other part 91 operations and parts 121, 125, 129, and 135 operations, the flight visibility is less than the visibility prescribed in the standard instrument approach procedure being used. |
§ 91.1039 IFR takeoff,
approach and landing minimums. (d) No person may take off an aircraft under IFR from an airport where weather conditions are at or above takeoff minimums but are below authorized IFR landing minimums unless there is an alternate airport within one hour's flying time (at normal cruising speed, in still air) of the airport of departure. |
135 |
§ 135.217 IFR: Takeoff limitations.
|
§ 135.221 IFR: Alternate airport weather minimums. No person may designate an alternate airport unless the weather reports or forecasts, or any combination of them, indicate that the weather conditions will be at or above authorized alternate airport landing minimums for that airport at the estimated time of arrival. |
121 |
§ 121.651 Takeoff and landing weather minimums: IFR: All certificate
holders.
|
§ 121.625 Alternate airport weather minimums.
|
7. DESIGNATING AN ALTERNATE
AIRPORT In any case, when an approach is not capable of being
used to support the airport being used as an alternate airport,
the procedure shall be appropriately annotated with reverse type "A" NA.
This is done whenever the airport is not served by a full-up weather
observation system or when a human observer is not available
[no weather available]. |
8.
ALTERNATE TAKE OFF MINIMUMS Alternate takeoff minimums ('A') are used to specify non-standard climb gradients when a standard rate climb will not clear obstructions. The non-standard climb gradient is specified so that the climbing aircraft will remain separated from the obstructions.
|
||
|
||
|
Thus, as a practical matter, if you are a commercial flight departing an airport that is IFR;
AND you can't determine any alternate airport within one hour's flight that is forecast to be above landing minimums,
AND your visibility is below the minimums for the lowest approach back to the departure airport (example above),
AND you can't meet either the standard or specified non-standard climb gradients (example below),
THEN you will need to see-and-avoid the mountains around the airport, if any.