Manual of the Medical Department (NAVMED P-117): Chapter 15: Medical Examinations: Special Duty

15-71A Landing Craft Air Cushion (LCAC) Crew Medical Standards

Department of the Navy
Bureau of Medicine and Surgery

(2) General. LCAC crew personnel include all individuals who, in the performance of their duties, are required to make operational w training missions aboard LCAC or any other U.S. Navy air cushion vehicle. LCAC crew personnel are divided into three classes:

(a) Class I. Crew personnel engaged in the actual control of the LCAC, which includes the craft master and engineer, as well as the student craft master and the student engineer.

(b) Class IA. Crew personnel engaged in navigation of the LCAC, but not responsible for actual control of the craft, to include the navigator and student navigator.

(c) Class II Crew personnel not engaged in the actual control of the LCAC, which includes load master, and deck mechanic, as well as student bad master, and student deck mechanic.

(3) Scope of Examination. Class I and Class IA LCAC crew candidates must meet the standards in article 1571A(5) and (6). Class II LCAC crew candidates must meet the standards in articles 15 71A (7). Conditions listed as disqualifying (see art. 15 71A(5), (6), and (7)) may be waived. However, additional medical tests, consultations, etc. are necessary in to confirm that no functional impairment is present w likely to occur (see art. 15 71A(9)).

(4) Examination Requirements

(a) Class I (Craftmaster, Engineer) Candidates. All Class I LCAC crew candidates will undergo an entrance physical examination at the designated LCAC medical examination center, the NAVAEROSPMEDINST (NAMI Code 26 before acceptance into Phase I of the LCAC training program. An SF 88 and SF 93 must be completed for all LCAC crew physical examinations. Class I candidates require psychomotor testing in addition to a physical examination. These psychomotor examinations will be performed in addition to the entrance physical examination at NAMI (Code 26). Candidates will be designated either:

(1) Physically qualified (PQ).

(2) Not physically qualified (NPQ).

(3) NPQ but waiver recommended.

(b) Class IA (Navigator) Candidates. All Class IA LCAC crew candidates will undergo an entrance physical examination at a sufficiently equipped military medical facility before acceptance into Phase I of the LCAC training program. An SF 88 and SF 93 must be completed for all LCAC crew physical examinations. Candidates will be designated either:

(1) Physically qualified (PQ).

(2) Not physically qualified (NPO).

(3) NPQ but waiver recommended.

(c) Class II (Loadmaster, Deck Mechanic) Candidates. Candidates for Class II LCAC crew training must meet current medical standards for transfer and sea duty following the Enlisted Transfer Manual (ETM).

(5) Class I (Craftmaster, Engineer) LCAC Crew Candidate Physical Examination and Standards

(a) General Examination. Except as modified by this article, the bask physical examination and standards for acceptance as an LCAC crew candidate are the same as those for enlistment.

(b) Additional Standards. In addition to general enlistment standards, presence or history of any of the following will be considered disqualifying for all LCAC duties, unless waived by proper authority (see an. 15 71A(9)).

(1) Ears, Nose, and Throat (ENT)

(a) Seasonal allergic rhinitis requiring medication or allergy immunotherapy for control.

(b) Recurrent attacks of vertigo (no waiver).

(c) Chronic or recurrent otitis externa or media.

(2) Eyes. Any ophthalmologic disorder that causes or that may progress to significantly degraded visual acuity.

(3) Lungs and Chest Wall. Recurrent spontaneous pneumothorax.

(4) Heart and Vascular

(a) History of cardiac surgery.

(b) Paroxysmal tachycardia or history thereof.

(c) Ventricular tachycardia.

(5) Abdominal Organs and Gastrointestinal (GI) System

(a) Peptic ulcer, gastric ulcer, or history thereof.

(b) Gastrointestinal hemorrhage or history

(c) Cholelithiasis.

(6) Endocrine and Metabolic Disorders. Hypoglycemia or history of any postprandial symptoms resembling those of postprandial syndrome (e.g., postprandial tachycardia, sweating, fatigue, or change in mentation).

(7) Genitalia and Genitourinary (GU) System. Recurrent renal calculus or a single episode of renal calculus with demonstrated structural abnormality or metabolic abnormality unresponsive to dietary therapy. A renal stone/metabolic workup must be performed if a history is given of a single prior episode of renal calculus with no other complicating factors.

(8) Extremities. Instability or restricted range of motion of the upper or lower extremities that could interfere with normal operation of foot pedals or ability to function in the LCAC environment.

(9) Spine

(a) Chronic or disabling back pain or history thereof.

(b) Herniated nucleus pulposus (HNP) or history thereof.

(c) Scoliosis with greater than 30 degrees thoracic or 20 degrees lumbar curvature.

(10) Neural Disorders

(a) History of unexplained or recurrent syncope.

(b) History of convulsive seizures of any type (except single simple seizure associated with febrile illness before age 5).

(c) Narcolepsy or history thereof.

(d) Any complicated head injury as outlined in section II of this chapter, including history of posttraumatic unconsciousness of 24 hours or more in duration, posttraumatic amnesia, penetrating head injury, or impaired judgment for 48 or more hours after injury.

(e) Encephalitis occurring 3 years or less prior to examination, meningitis occurring within 1 year of examination, or either disease resulting in neurological sequelae or abnormal neurologic examination.

(f) History of recurrent, incapacitating headache or facial pain or any headache associated with impairment of motor, sensory, visual, or other neurologic function.

(11) Psychiatric

(a) Any history of psychosis, eating disorder, or AXIS II disorder of the DSM IIIR must be disqualifying (no waivers).

(b) Other major AXIS I disorders including mood, anxiety, and somatoform disorders must be considered disqualifying but waiverable if the individual has been symptom free without treatment for at least 1 year.

(c) Alcohol or drug abuse disqualifying. Upon satisfactory completion of accepted substance abuse program and total compliance with aftercare program, a waiver may be considered providing 1 year has elapsed post treatment. Continuation of a waiver would be contingent upon continued compliance with aftercare program as well as total abstinence.

(d) Any evidence of anticipated poor adaptability to LCAC duty conditions (claustrophobia, questionable judgment or affect, or poor stress coping skills) is considered disqualifying and requires a psychiatric consultation to consider waiver.

(12) Systemic Disease and Miscellaneous Conditions

(a) Motion sickness, severe or incapacitating or history thereof.

(b) Recurrent or chronic joint pain or swelling or diagnosed arthritis.

(c) History of heat pyrexia (heat stroke), or documented predisposition to this condition (including disorders of sweat mechanism), or any history of malignant hyperthermia.

(c) Clarification of Procedure and Standards.

(1) General Fitness/Medications. A notation will be recorded on the SF-88 and SF 93 for individuals receiving medications on a regular basis or within 24 hours of the LCAC examination. In general, individuals requiring medications or whose general fitness might affect their LCAC control proficiency shall not be found qualified for duty aboard the LCAC. Record in box 77 of the individual's SF 88 (e.g., NPQ LCAC Duty).

(2) Height and Weight. All candidates will meet acceptable body fat percentages as per OPNAVINST 6110.1 series. The maximum acceptable body fat percentages for males is Z percent and for females is 30 percent.

(3) Cardiovascular System. History or presence of cardiac arrhythmia, heart murmur, or other evidence of cardiac abnormality is cause for medical referral for clearance for LCAC duty.

(4) Blood Pressure and Pulse Rate

(a) Blood Pressure. Blood pressure is determined first after the examinee has been supine for at least 5 minutes and second after standing motionless for 3 minutes. A persistent systolic blood pressure of 140 mm or more is disqualifying, and a persistent diastolic blood pressure of 90 mm or more is disqualifying.

(b) Pulse Rate. Pulse rate is determined first after the examinee has been recumbent at least 5 minutes and second after standing motionless for 3 minutes (both determinations to coincide with the measurement of blood pressure). An ECG must be obtained in the presence of a relevant history, arrhythmia, or pulse of less than 50 or greater than 110. Resting poise shall not persistently exceed 100; standing pulse shall not exceed 110.

(5) Electrocardiogram (ECG). All candidates must have a 1 2 lead standard ECG performed at the time of their entrance physical examination. The baseline ECG must be marked Not To Be Removed From Health Record and must be retained in the individual's health record until that record is permanently closed. Each baseline ECG, or copy thereof, shall bear adequate identification data including the individual's full name, grade or rate, social security number, and designator.

(6) Teeth

(a) Dental Class 1 and Class 2 are considered as qualifying.

(b) If a candidate is dental Class 3 due only to periodontal status not requiring surgery, the candidate will be accepted as qualified after obtaining a dental waiver.

(7) Articulation. Candidates must speak clearly and distinctly without accent or impediment of speech that would interfere with radio conversation. Use the Read Aloud Test in art. 15 23 for this determination.

(8) Mental Naval Review. A mental health review covering the psychiatric items in art. 15 71A(5)(b)(11) and any other pertinent personal history items must be conducted by the medical officer responsible for that candidate's physical examination. A psychiatric referral is not required to obtain this history. This general mental health review will determine the individual's bask stability, motivation, and capacity to maintain acceptable performance under the special stresses encountered during LCAC operation.

(9) Neurological Examination. A careful and complete neurological examination must be made. Any neurologic defect which may interfere with LCAC duty requires a neurology consultation.

(10) Distant Visual Acuity. For the entrance physical examination, determine visual acuity by using a 20-foot eye lane with standard Goodlite letters. The Armed Forces Vision Tester (AFVT) is an alternate acceptable method. If corrective lenses are necessary for LCAC duty, the LCAC crew personnel must be issued the approved lens hardened eye glasses for proper interface with operational headgear (i.e., aviation frames). A spare pair of corrective lenses must be carried at all times during operations. For Class I person nel, minimum distant visual acuity must be no less than 20/100 uncorrected each eye and correctable to 20/20 each eye. H correction is necessary for LCAC personnel, corrective lenses must be wan at all times during LCAC operation.

(11) Near Visual Acuity. The AFVT or the near vision testing card must be used to test near vision. A minimum near vision acuity of 20/20 in each eye, correctable to 20Q0, is acceptable. H correction is necessary, corrective lenses must be worn at all times during LCAC operations.

(12) Radiation. Refraction of the eyes must be required on the initial candidate screening examination if the candidate requires corrective lenses to meet the visual acuity standards. For Class I personnel, acceptable limits are +5.5D in any meridian. The difference in the refractive errors in any meridian of the two eyes (anisometropia) may not exceed 3.5D. Cylinder correction may not exceed 3.0D.

(13) Depth Perception. This test should be performed using a Verhoeff stereopter. Pass Fail standards per art. 15 65 (7) must be followed. Normal depth perception is acceptable (aided or unaided). H visual correction is necessary for normal depth perception, corrective lenses must be worn at all times during LCAC operation.

(14) Oculomotor Balance. The vertical and lateral phorias may be tested with the phorometer a with the AFVT. Any lateral phoria greater than 10 prism diopters is disqualifying (greater than 6 prism diopters requires an ophthalmologic consultation). Any vertical phoria greater than 1.5 prism diopters is disqualifying (any vertical phoria greater than 1.0 prism diopters should receive an ophthalmologic consultation).

(15) Inspection of the Eyes. Follow art. 15-65(7). The examination must include a funduscopic examination. Any pathological condition that might become worse or interfere with the proper functioning of the eyes under fatigue or LCAC operating conditions shall disqualify the candidate.

(16) Color Vision. Class I crew personnel must pass the Farnsworth Lantern Test.

(17) Night Vision. Any indication or history of night blindness disqualifies the candidate due to the importance of night vision to LCAC operations.

(18) Field of Vision. Normal fields should be full to confrontation, see art. 15 40. Any visual field detect should receive ophthalmologic referral to rub out underlying pathology

(19) Intraocular Tension. Schiotz, noncontact ("air puff"), or applanation tonometry must be used to measure intraocular tension. Tonometric readings consistently above 20 mm Hg Schiotz in either eye, or a difference of 5 mm Hg Schiotz between the two eyes, should receive an ophthalmologic referral for further evaluation. This condition is disqualifying until ophthalmologic evaluation has been completed. Subsequent medical clearance is based on said ophthalmologic evaluation.

(20) Ears. Follow article 15 39(1). General enlistment standards in article 15 39 are accepted as candidate standards, with the exception of audiometric standards. Any disqualifying acute ear disease a disorder by those standards disqualifies the candidate.

(21) Hearing Tests. An audiogram is required for all LCAC Class I candidates. An audiogram will also be performed within 90 days of reporting to the assigned assault craft unit, and annually thereafter. Audiometric loss in excess of the following limits for each frequency disqualifies the candidate.

Maximum Hearing Loss (ANSI 1969)

Freq (Hz)	Better Ear (dB)	Worse Ear (dB)
500 1000 2000	35 30 30	35 50 50

(22) Equilibrium. Use the self-balancing test (SBT). The examinee stands erect, without shoes, with heels and large toes touching. The examinee then flexes one knee to a right angle, closes the eyes, then attempts to maintain this position fa 15 seconds. The results of the test are recorded as "steady," "fairly steady," "unsteady," or "failed." Inability to pass this test fa satisfactory equilibrium disqualifies the candidate.

(6) Class IA (Navigator) Candidate Physical Examination and Standard

(a) General Examination. Except as modified by this article, the basic physical examination and basic physical standards for acceptance as an LCAC crew candidate are the same as those prescribed for enlistment.

(b) Additional Standards for Class IA personnel. The additional physical standards required for Class I personnel are also required for Class IA. The following exceptions apply:

(1) As stated in article 15 71A(4)(b), the entrance physical examinations for Class IA personnel may be performed at any sufficiently equipped and staffed military medical facility, and are not limited to designated LCAC medical examination centers.

(2) Psychomotor testing is not required for Class IA crew candidates.

(3) Distant Visual Acuity: Minimal uncorrected distant visual acuity for Class IA personnel must be no less than 20/200 each eye, correctable to 20/20. If correction is necessary, corrective lenses must be worn at all times during LCAC operations.

(7) Class II (Loadmaster, Deck Mechanic) Candidate Physical Examination and Standards. The basic physical examination standards for enlistment are acceptable for Class II LCAC crew candidates. However, each LCAC crew candidate must have a current (within 5 years) physical examination on record and the candidate must meet the physical requirements for general duty. The presence or history of any medical problems will be considered disqualifying for Class II LCAC duties, unless waived by proper authority (see art. 15 71A(9)).

(8) Development of Mandatory Requirements for LCAC Crew Members Who Have Been Medically Suspended From LCAC Duty

(a) There are currently no standards regarding LCAC crew members medically suspended for an extended period from LCAC operations to (1) declare them NPQ from LCAC duty or (2) to make it mandatory for that member to request a medical waiver for the condition causing prior suspension.

(b) Recommend setting 30 days as a time limit for limited or medically restricted duty after which the crew member must be evaluated by a medical officer to determine whether that individual is NPQ for LCAC duty, should be recommended for a medical waiver (see art. 15 71A(9)), or should undergo a medical board.

(9) Medical Waiver Requests

(a) Class I LCAC Crew Candidates. Forward medical waiver requests for Class I crew candidates to the Bureau of Naval Personnel (PERS 409C) from the Naval Aerospace Medical Institute (NAMI, Code 26). A copy of all approved waivers must be sent from PERS 409C to NAMI (Code 26) for archival purposes.

(b) Class IA & II LCAC Crew Candidates. Forward medical waiver requests for Class IA and Class II crew candidates to PERS 409C via the TYCOM medical officer. A copy of Class IA and Class II approved waivers must be sent from PERS 409C to NAMI (Code 26) for archival purposes.

(c) Medically suspended LCAC Crew Personnel. Forward medical waiver requests for LCAC crew personnel who are medically suspended to the TYCOM medical officer via the chain of command. The TYCOM medical officer must evaluate and approve medical waiver requests for designated LCAC crew personnel (as opposed to LCAC crew candidates). A copy of the TYCOM medical officer's final decision, either an approval or disapproval, concerning the waiver request will be forwarded to NAMI (Code 26) for archival purposes.

(10) Periodic Physical Examinations

(a) All LCAC Class I and Class IA crew personnel will undergo a complete physical examination (using SF 88 and SF 93) within 30 days of the anniversary of their birth at ages 21,24, 27, 30, 33, 36, and 39 and annually thereafter.

(b) All LCAC Class II personnel will undergo a complete physical examination within 30 days of the anniversary of their birth every 5 years.

(11) Reporting Attrition of LCAC Crew Personnel. Critical to the evolution of the LCAC crew evaluation process is the development of accurate personnel data bases, in particular, attrition of LCAC crew personnel. Therefore, all such attritions, medical and nonmedical, are to be reported to NAMI (Code 26) for archival purposes.