Petition for Rulemaking: Removal of F/A-18 from list of aircraft 

“Limited-to-Center Thrust”.

Introduction

FAA order 8900.1 Volume 5, Section 4, item 5-88 lists the F/A-18 as an 

aircraft in which a military pilot may only receive a multiengine 

operator or instructor rating “Limited-to-Center Thrust”. The reason 

stated is that “no published data on VMC” has been provided by the 

manufacturer. As an active test pilot with a Specialized Master’s 

degree in Experimental Flight Test Engineering, I intend to show

through flight manual excerpts that the F/A-18 not only has published 

VMC data, but that it is a suitable platform in which to conduct a 

multiengine practical test with respect to VMC tasks in accordance with 

14 CFR Part 61.45 and the Practical Test Standards. The intent of 

this petition is to allow military qualification in the F/A-18 to 

transfer to an unrestricted multiengine qualification at the 

commercial pilot and instructor level.

VMC Defined

First, I will show that the NATOPS flight manual for F/A-18, A1-F18EANFM-000, clearly defines single engine minimum control speed (VMC) in 

keeping with the intentions of 14 CFR Part 23.149.

Chapter 11: Flight Characteristics states: “Single engine minimum 

control speed (VMC) is defined as the minimum airspeed required to 

maintain controlled flight with one engine operating. VMC airspeeds 

were determined at 14° AOA (angle of attack) for catapult launches, 

and 12° AOA for all other circumstances. VMC airspeed varies depending 

on AOA, lateral asymmetry, altitude, and day temperature.” Further 

along in the flight manual under the discussion of shipboard 

emergencies: “Catapult launch bulletins ensure an end-speed at least 

15 knots above minimum controllable airspeed. VMC numbers for the F/A18 E/F launch bulletins are defined at 14° AOA.” Further clarifying 

VMC and its importance, Chapter 8: Carrier-Based Procedures continues 

the discussion of VMC with respect to catapult launches and minimum 

airspeed required for safe flight: “Minimum catapult launch endspeeds are governed by three limiting factors: Flaps FULL, minimum 

single engine control speed (VMC), maximum longitudinal acceleration 

capability, and sink-off-bow. VMC is the airspeed below which the 

aircraft is not controllable with a single engine failure. The VMC

airspeed governs the end-speed for most of the gross weight range in 

both MIL and MAX power (up to 60K MIL and 65K MAX, see figure 8-1, 

Table B). VMC is also a function of lateral weight asymmetry; 

therefore, end-speed must be increased for asymmetric loadings (see 

figure 8-1, Table C).” These sections and tables are included as 

attachments.

The textbook Aerodynamics for Naval Aviators, NAVWEPS 00-80T-80, 

defines minimum directional control speed as “simply the equivalent 

airspeed (or dynamic pressure) to produce a required yawing moment 

with the maximum rudder deflection.” Recall that equivalent airspeed 

accounts for compressibility effects and is a correction to calibrated 

airspeed not displayed to the pilot. 14 CFR Part 23.149 defines the 
regulatory VMC as a calibrated airspeed, which is only equal to 

equivalent airspeed at standard-day sea level conditions. When in the 

takeoff or landing configuration, F/A-18 aircraft are flown 

referencing angle of attack to compensate for varying atmospheric 

conditions and aircraft configuration (weight and asymmetry). The 

F/A-18 displays calibrated airspeed to the pilot, but AOA is the 

primary reference in the shipboard environment. The calculation from 

a VMC in equivalent airspeed to calibrated airspeed becomes unnecessary 

when angle of attack is utilized. Due to the myriad aircraft 

configurations and the critical procedural timing of an engine failure 

during a catapult launch, it is inappropriate to define a single VMC

number in knots of calibrated airspeed because of the aforementioned

errors. 

If a pilot, however, wishes to determine the VMC value in knots 

calibrated airspeed (KCAS), it is simply referenced in tables provided 

based on weights and asymmetry. These tables assume a standard day 

and have corrections for non-standard conditions. For a practical 

example, we will assume a catapult launch at 50,000 pounds gross 

weight with little to no asymmetry, where VMC is the critical factor 

determining safe end-speed. Referring to Table B, we find 153 KCAS 

for minimum end-speed, which equates to MINIMUM SPEED, VMC, plus a 15 

knot safety factor. Referencing the attached Catapult Launch 

Bulletin, Figure 3, we verify that the stated MINIMUM SPEED for 

weights up to 50,000 pounds, VMC, is equal to 138 knots (153 minus 15). 

The Catapult Launch Bulletin verifies the VMC data found in the flight 

manual discussion on minimum speeds. This procedure may be followed 

for other aircraft gross weights, with a separate table for outside 

air temperature, in order to correlate 14° AOA with a value in knots 

calibrated airspeed.

The F/A-18, thus, meets the requirement of FAA order 8900.1 Volume 5 

Chapter 1 Section 4, 5-88E (2) which requires VMC data to be published 

in the approved flight manual. 

VMC and Emergency Procedures

Now that VMC has been defined for the F/A-18, we will investigate 

various emergency procedures for the aircraft and how VMC is addressed

in operations. 

During an emergency catapult flyaway, where an engine has failed, the 

immediate action steps are as follows:

1. Throttles – MAX

2. Rudder – Full against yaw/roll

3. Emergency jettison button – PUSH

4. Maintain 10° to 12° pitch attitude with waterline symbol

**Do not exceed 14° AOA (AOA warning tone)

5. If unable to arrest yaw/roll or stop settle – EJECT
Just as a Part 23-certified aircraft’s procedure states to maintain 

airspeed above VMC, the F/A-18 procedure states to maintain AOA below 

VMC AOA. In the discussion section of this emergency, the flight 

manual reiterates that VMC is defined at 14° AOA and that 

“controllability should be sufficient if airspeed is above VMC.” It is 

worth noting that single-engine controllability is guaranteed above 

VMC, not a positive climb rate.

A single engine failure during a runway takeoff and the decision to 

abort or continue is subject to Minimum Go Speed charts, which is a 

hybrid of the regulatory speeds V1 and V2. Since the F/A-18 is a high 

thrust-to-weight aircraft, the abort/continue decision is typically 

made based on runway remaining to safely stop. If an engine fails on 

takeoff and takeoff is continued, the emergency procedure states to 

maintain “on speed, balanced flight” as a higher restriction than VMC. 

On speed angle of attack in the F/A-18 is 8.1° and provides the 

greatest amount of lift with flaps in HALF or FULL. A deceleration 

toward VMC would not only reduce climb performance, but introduce 

controllability problems.

During up and away or cruise flight, with flaps in AUTO, the F/A-18 

displays excellent handling qualities thanks to its fully digital 

flight control system. Chapter 11 of the flight manual describes that 

an engine failure in this mode “results in no degradation in handling 

qualities under most circumstances at low AOA.” “At high AOA, engine 

failure results in a yaw toward the failed engine that is controllable 

by quickly reducing AOA and countering the yaw with rudder.” Since no 

takeoff or landing is made with flaps in AUTO position, there is no 

requirement for a VMC demonstration in this configuration.

The F/A-18 as a suitable platform

Under FAA order 8900.1 Volume 5 Chapter 1 Section 4, 5-88F Removal of 

Limited-to-Center Thrust Limitation From the Airplane Multiengine Land 

Rating, various tasks must be demonstrated in a suitable airplane at 

the commercial pilot level. All of these tasks are addressed in the 

F/A-18 flight manual, annual NATOPS check flights and Instructor check 

flights.

 Principles of Flight – Engine Inoperative

 Engine Failure During Takeoff Before VMC (Simulated)

 Engine Failure After Lift-Off (Simulated)

 Approach and Landing with an Inoperative Engine (Simulated)

 Maneuvering with One Engine Inoperative

 VMC Demonstration

The F/A-18 emergency procedures are typically built on the premise of 

flying to on-speed AOA during an engine failure to ensure maximum lift 

and the first five of these tasks are executed at that speed, 8.1° 

AOA. These EPs may be practiced during flight as on-speed AOA 
provides sufficient margin to VMC. I will not expand on these tasks as 

they are no particular concern to the VMC discussion.

The VMC demonstration is thoroughly addressed through simulators. The 

Practical Test Standards for a multiengine pilot describe the VMC

demonstration maneuver as a slow approach toward VMC while configured 

for takeoff. It also indicates that due to VMC being lower at 

altitude, recovery shall be made at the first indication of loss of 

directional control, stall warning or buffet. Recall that VMC is truly 

expressed in equivalent airspeed and is lower at altitude due to 

compressibility errors not accounted for in calibrated or indicated 

airspeed. For F/A-18 compliance, the VMC procedures are demonstrated

in the simulator after a low-airspeed catapult launch combined with an 

engine failure. Execution of the immediate action items previously 

discussed results in a recoverable scenario, as long as AOA is 

maintained below VMC and sufficient thrust is available. The ejection 

decision is often tested when airspeed is less than VMC and not all 

training scenarios are recoverable. During a flight demonstration, 

intentional departures are prohibited in the F/A-18, but a slow 

approach to stall warning, also 14° AOA, may be executed with one 

engine at idle power. This technique is in full compliance with the 

Practical Test Standards.

Public Benefit

Removal of this restriction will benefit the public interest by 

allowing qualified military pilots to more easily transition into the 

civilian sector. As there is not an instructor certification for 

Multiengine Limited-to-Center Thrust, an F/A-18 instructor pilot is 

unable to transition to civilian instruction without great time and 

financial burdens. During basic aircraft transition, an F/A-18 pilot 

will be able to easily transition between an AOA-referenced Vmc to one 

in knots calibrated airspeed, as most civilian aircraft are not 

equipped with AOA. Due to time-in-model minima on multi-engine 

instruction, there is not a compelling reason to limit an F/A-18 

instructor pilot to be certified as a multi-engine instructor.

Conclusion

I have demonstrated that the F/A-18 has well-defined, published VMC

data and that it more than meets the intent of 14 CFR Part 23.149 

definitions as it accounts for both compressibility errors and 

aircraft configuration. This alone meets the requirement to remove 

F/A-18 from the list of airplanes limited to center thrust. In 

addition, the aircraft is suitable to accomplish the tasks delineated 

for multiengine pilots and instructors in the Practical Test 

Standards. Military competency based on the F/A-18 should result in a 

multiengine rating without restriction at the commercial and 

instructor level. 

Footnote

It is not cited in my petition, but I have also attached a paper 

published by the Society of Experimental Test Pilots describing the VMC
testing approach and changes made to the flight controls following a 

loss of control and near-mishap.

For additional details from Boeing, you may also contact Boeing’s lead

test pilot for F/A-18, Mr. Michael Wallace at (301) 757-4202 or 

Michael.m.wallace@boeing.com.

Very respectfully,

Jeremy DeBons

Lieutenant

Test Pilot

United States Navy