Source: https://www.federalregister.gov/documents/2009/12/04/E9-28896/special-conditions-embraer-sa-model-emb-505-flight-performance-flight-characteristics-high-speed
Timestamp: 2019-06-18 16:48:02
Document Index: 701042315

Matched Legal Cases: ['art 23', 'art 23', 'art 25', 'art 25', 'art 23', 'art 23', 'art 23', '§\u200923', '§\u200923', '§\u200923', '§\u200923', '§\u200923', '§\u200923', '§\u200923', 'art 23', 'art 23', '§\u200923', 'art 23', '§\u200923', '§\u200923', '§\u200923', '§\u200923', '§\u200923', '§\u200923', '§\u200923', '§\u200923', '§\u200923', '§\u200923', '§\u200923', '§\u200923']

Federal Register :: Special Conditions: Embraer S.A. Model EMB-505; Flight Performance, Flight Characteristics, High Speed Conditions, and Operating Limitations
Special Conditions: Embraer S.A. Model EMB-505; Flight Performance, Flight Characteristics, High Speed Conditions, and Operating Limitations
The effective date of these special conditions is November 25, 2009.
74 FR 63560
63560-63563 (4 pages)
Docket No. CE302
Special Conditions No. 23-242-SC
E9-28896
https://www.federalregister.gov/d/E9-28896 https://www.federalregister.gov/d/E9-28896
These special conditions are issued for the Embraer S.A. Model EMB-505 airplane. The EMB 505 is an all-new, high-performance, sweep wing, twin turbofan powered aircraft. This airplane will have a novel or unusual design feature(s) which include turbofan engines, aft engine location, new avionics, a trimmable horizontal tail, and performance characteristics inherent in this type of airplane that were not envisioned by the existing regulations. In addition, this airplane is a jet airplane being certificated in the commuter category by exemption. The applicable airworthiness regulations do not contain adequate or appropriate safety standards for this design feature. These special conditions contain the additional safety standards that the Administrator considers necessary to establish a level of safety equivalent to that established by the existing airworthiness standards.
We must receive your comments by January 4, 2010.
Mail two copies of your comments to: Federal Aviation Administration, Regional Counsel, ACE-7, Attn: Rules Docket No. CE302, 901 Locust, Kansas City, Missouri 64106. You may deliver two copies to the Regional Counsel at the above address. Mark your comments: Docket No. CE302. You may inspect comments in the Rules Docket weekdays, except Federal holidays, between 7:30 a.m. and 4 p.m.
J. Lowell Foster, Federal Aviation Administration, Aircraft Certification Service, Small Airplane Directorate, ACE-111, 901 Locust, Room 301, Kansas City, Missouri 64106; 816-329-4125, fax 816-329-4090.
On October 9, 2006, Embraer S.A. applied for a type certificate for their new Model EMB-505. The Model EMB-505 is a commuter category, low-winged monoplane with “T” tailed vertical and horizontal stabilizers, retractable tricycle type landing gear and twin turbofan engines mounted on the aircraft fuselage. Its design characteristics include a predominance of metallic construction. The maximum takeoff weight is 17,967 pounds, the VMO/MMO is 320 KCAS/M 0.78 and maximum altitude is 45,000 feet.
For the past decade, the Federal Aviation Administration (FAA) has applied special conditions to jets. The Start Printed Page 63561special conditions have varied based on the jet's performance, but in general jets weighing more than 6,000 lbs. have had the commuter category performance requirements applied. Since this is a commuter category airplane, most of the existing jet special conditions are contained in part 23 and already apply. Existing part 23 flying qualities requirements tend to provide a higher level of safety than part 25 (to address a lower pilot skill base), so there is little change needed for jets except for the allowance of turbojet related terms such as VFC/MFC and VDF/MDF. Special conditions for flying qualities, stability, and control also reflect speed ranges appropriate for this class of jet. High speed conditions including flutter, vibration, and high speed characteristics have been applied to jets depending on their speed range and configuration. Since the EMB Model 505 will have a trimmable horizontal tail, operate above 25,000 ft., and have a MD greater than M0.6, it will have all of the high speed special conditions applied to it. These special conditions come directly from part 25.
Several 14 CFR part 23 paragraphs have been replaced by or supplemented with special conditions. These special conditions have been numbered to match the 14 CFR part 23 paragraph they replace or supplement. Additionally many of the other applicable part 23 paragraphs cross-reference paragraphs that are replaced by or supplemented with special conditions. For example, § 23.141 states, “The airplane must meet the requirements of § 23.143 through § 23.253 * * *” Within this range of paragraphs, there are special conditions associated with § 23.177, § 23.203, § 23.252, and § 23.253. The special conditions associated with these paragraphs supersede the original paragraphs and must be applied. This principle applies to all part 23 paragraphs that cross-reference paragraphs associated with special conditions.
Under the provisions of 14 CFR part 23 § 23.141, Embraer S.A. must show that the Model EMB-505 meets the applicable provisions of 14 CFR part 23, as amended by §§ 23.143 through 23.253, thereto.
Flight Performance, Flight Characteristics, High Speed Conditions, and Operating Limitations.
As discussed above, these special conditions are applicable to the Model EMB-505. Should Embraer S. A. apply at a later date for a change to the type certificate to include another model incorporating the same novel or unusual design feature, the special conditions would apply to that model as well.
Under standard practice, the effective date of final special conditions would be 30 days after the date of publication in the Federal Register; however, as the certification date for the Embraer S. A. Model EMB-505 is imminent, the FAA finds that good cause exists to make these special conditions effective upon issuance.
Accordingly, pursuant to the authority delegated to me by the Administrator, the following special conditions are issued as part of the type certification basis for the Embraer S. A. Model EMB-505 airplanes.
The following special conditions will apply:
1. SC 23.177 Static directional and lateral stability.
(a) The static directional stability, as show by the tendency to recover from a wings level sideslip with the rudder free, must be positive for any landing gear and flap position appropriate to the takeoff, climb, cruise, approach, and landing configurations. This must be shown with symmetrical power up to maximum continuous power, and at speeds from 1.2 VS1 up to VFE, VLE, or VFC/MFC (as appropriate). The angle of sideslip for these tests must be appropriate to the type of airplane. At larger angles of sideslip, up to that at which full rudder is used or a control force limit in § 23.143 is reached, whichever occurs first, and at speeds from 1.2 VS1 to VO, the rudder pedal force must not reverse.
(b) The static lateral stability, as shown by the tendency to raise the low wing in a sideslip, must be positive for all landing gear and flap positions. This must be shown with symmetrical power up to 75 percent of maximum continuous power at speeds above 1.2 VS1 in the takeoff configuration(s) and at speeds above 1.3 VS1 in other configurations, up to VFE, VLE, VNO, or VFC/MFC (as appropriate) for the configuration being investigated, in the takeoff, climb, cruise, and approach configurations. For the landing configuration, the power must be that necessary to maintain a 3 degree angle of descent in coordinated flight. The static lateral stability must not be negative at 1.2 VS1 in the takeoff configuration, or at 1.3 VS1 in other configurations. The angle of sideslip for these tests must be appropriate to the type of airplane, but in no case may the constant heading sideslip angle be less than that obtainable with a 10 degree bank, or if less, the maximum bank angle obtainable with full rudder deflection or 150 pound rudder force.
(c) In straight, steady slips at 1.2 VS1 for any landing gear and flap positions, and for any symmetrical power conditions up to 50 percent of maximum continuous power, the Start Printed Page 63562aileron and rudder control movements and forces must increase steadily, but not necessarily in constant proportion, as the angle of sideslip is increased up to the maximum appropriate to the type of airplane. At larger slip angles, up to the angle at which the full rudder or aileron control is used or a control force limit contained in § 23.143 is reached, the aileron and rudder control movements and forces must not reverse as the angle of sideslip is increased. Rapid entry into, and recovery from, a maximum sideslip considered appropriate for the airplane must not result in uncontrollable flight characteristics.
2. SC 23.181 Dynamic stability.
Instead of compliance with § 23.181(d), the following apply:
(d) During the conditions as specified in § 23.175, when the longitudinal control force required to maintain speeds differing from the trim speed by at least plus and minus 15 percent or 15 kts, whichever is less, is released, the response of the airplane must not exhibit any dangerous characteristics nor be excessive in relation to the magnitude of the control force released. Any long-period oscillation of flight path, phugoid oscillation, that results must not be so unstable as to increase the pilot's workload or otherwise endanger the airplane.
3. SC 23.201(e) Wings level stall.
Instead of compliance with § 23.201(e), the following apply:
(2) Thrust-
(ii) The thrust necessary to maintain level flight at 1.6VS1 (where VS1 corresponds to the stalling speed with flaps in the approach position, the landing gear retracted, and maximum landing weight).
(3) Trim at 1.4VS1 or the minimum trim speed, whichever is higher.
4. SC 23.203(c) Turning flight and accelerated turning stalls.
5. SC 23.251 Vibration and buffeting.
(b) Each part of the airplane must be shown in flight to be free from excessive vibration under any appropriate speed and thrust conditions up to VDF/MDF. The maximum speeds shown must be used in establishing the operating limitations of the airplane in accordance with special condition § SC 23.1505.
6. SC 23.253 High speed characteristics.
(2) Allowing for pilot reaction time after effective inherent or artificial speed warning occurs, it must be shown that the airplane can be recovered to a normal attitude and its speed reduced to VMO/MMO, without:
(b) Maximum speed for stability characteristics, VFC/MFC. VFC/MFC is the maximum speed at which the requirements of § 23.175(b)(1), special condition § SC 23.177, and § 23.181 must be met with flaps and landing gear retracted. It may not be less than a speed midway between VMO/MMO and VDF/MDF except that, for altitudes where Mach number is the limiting factor, MFC need not exceed the Mach number at which effective speed warning occurs.
7. SC 23.255 Out-of-trim characteristics.
(b) In the out-of-trim condition specified in paragraph (a) of this special condition, when the normal acceleration is varied from +l g to the positive and negative values specified in paragraph Start Printed Page 63563(c) of this special condition, the following apply:
(e) During flight tests required by paragraph (a) of this special condition, the limit maneuvering load factors, prescribed in §§ 23.333(b) and 23.337, need not be exceeded. Also, the maneuvering load factors associated with probable inadvertent excursions beyond the boundaries of the buffet onset envelopes determined under special condition SC 23.251(e), need not be exceeded. In addition, the entry speeds for flight test demonstrations at normal acceleration values less than 1 g must be limited to the extent necessary to accomplish a recovery without exceeding VDF/MDF.
(f) In the out-of-trim condition specified in paragraph (a) of this special condition, it must be possible from an over speed condition at VDF/MDF to produce at least 1.5 g for recovery by applying not more than 125 pounds of longitudinal control force using either the primary longitudinal control alone or the primary longitudinal control and the longitudinal trim system. If the longitudinal trim is used to assist in producing the required load factor, it must be shown at VDF/MDF that the longitudinal trim can be actuated in the airplane nose-up direction with the primary surface loaded to correspond to the least of the following airplane nose-up control forces:
8. SC 23.1323 Airspeed indicating system.
Instead of compliance with § 23.1323(e), the following apply:
(e) In addition, the airspeed indicating system must be calibrated to determine the system error during the accelerate-takeoff ground run. The ground run calibration must be determined between 0.8 of the minimum value of V1 to the maximum value of V2, considering the approved ranges of altitude and weight. The ground run calibration must be determined assuming an engine failure at the minimum value of V1.
9. SC 23.1505 Airspeed limitations.
Instead of compliance with § 23.1505, the following apply:
(a) The maximum operating limit speed (VMO/MMO-airspeed or Mach number, whichever is critical at a particular altitude) is a speed that may not be deliberately exceeded in any regime of flight (climb, cruise, or descent), unless a higher speed is authorized for flight test or pilot training operations. VMO/MMO must be established so that it is not greater than the design cruising speed VC/MC and so that it is sufficiently below VD/MD or VDF/MDF, to make it highly improbable that the latter speeds will be inadvertently exceeded in operations. The speed margin between VMO/MMO and VD/MD or VDF/MDF may not be less than that determined under § 23.335(b) or found necessary in the flight test conducted under special condition § SC 23.253.
Issued in Kansas City, Missouri, on November 25, 2009.
[FR Doc. E9-28896 Filed 12-3-09; 8:45 am]