[B Horiz Sit right HAC

HORIZ SIT display (PFS) 4 I XX X X SITE PHI X X X X X S rc XXXXX TAG X X K XX X D Q Q M H MM S5 BP6 C(5b HH .MM SS NAV DELTA AX 10 ItliiKSXi. Ar ii tdxxxxxx A V 1 A l XXXX A I 15 Itjxxxx LOAD I 5 E T Ji l KX TAC1 XXXTAC2 XXX TAG 3 XXX iXXX XXSiXXX .XXSiXXX .xxs XXX XXSJiXXX .xxs+xxx . xxs

[D Horiz Sit BFS

HORIZ SIT display (BFS) Figure 5-16. HORIZ SIT display (BFS) 4. Item 6 (G& N) provides the capability to designate the alternate HAC to be used for targeting during entry. Text (OVHD or STRT) is displayed next to item 6 to indicate whether the approach is to be overhead or straight-in. The display is initialized in MM 101 with OVHD selected and does not change unless the crew selects the alternate HAC in MM 304, 305, 602, or 603. In addition, indicators are provided for GN& C...

Figure Override display PFS

Item 41 allows the crew to override an RCS manifold valve microswitch dilemma that has forced RCS RM to set the valve status to closed. This dilemma may prevent some good jets from being used and reduce the FCS capability. Execution of item 41 causes RCS RM to set the valve status to open on any item in dilemma and puts the RCS jets (ones without previous OFF or LK failures that have not been overridden) back into the jet availability table. 2. For each of the IMU LRU's, data are displayed...

Nominal Burn Procedures

At TIG, the crew starts a timer and verifies OMS ignition by checking the OMS chamber pressure increases to approximately 104 percent, and the four OMS engine valves open to approximately 100 percent. During the burn, the crew monitors AVTOT, TGO, and orbiter weight decreasing and good attitude control on the ADI. Two seconds after the engines shut down, the OMS engine switches are turned off. The 2-second delay allows time for a nitrogen purge of the engines. The VGO (X and Z) residuals are...

Nominal Procedures

The main unique procedure in the 1 engine deorbit burn is starting the burn with the failed OMS engine propellant crossfed to the good OMS engine. A return to straight feed must be done at the proper time during the burn to balance the propellant remaining on each side, for Y c.g. control. Both AVTOT and percent quantity cues are available. The percent quantity cue includes the side to be monitored (L or R), the propellant to be monitored (FU or OX), and the percent quantity to return to...

Info

L,R OMS TK ISOL (four) - OP XFEED (four) - CL OMS PRPLT FAIL CONTINUE BURN Secure aff OMS ITEM 18 +0 EXEC vADI - LVLH, center needles Interconnect good OMS to RCS THC +X(vOMS vs RCS Burn Time) AFT RCS RECONFIG RCS COMPLETION vADI - LVLH, center needles Interconnect good OMS to RCS THC +X(vOMS vs RCS Burn Time) RCS I'CNCT TK SW THC +X(vOMS vs RCS Burn Time) AFT RCS RECONFIG RCS COMPLETION CONTINUE BURN ITEM 18 +0 EXEC I G23 I Resel jets Figure 4-9. DEORBIT BURN (1 ENG) cue card

Oms Eng Fail

* Failed OMS ENG - OFF ,_,_,_, * * OMS XFEED at 1 2 AVTOT at fail I I I I * * or OMS QTY I I I L or I I I R * Once the failed engine is turned off, guidance recomputes for a single-engine burn with a resulting change in orbiter burn attitude and error needle configuration. When the crew is satisfied that this reconfiguration has been successfully accomplished, the next procedure is to start crossfeeding OMS propellant from the side of the failed engine at the proper time to ensure a good Y c.g....

Bias Readout

As discussed in a previous section, the H bias term displayed digitally on the ENTRY TRAJ displays is a feedback correction term calculated by guidance. Before the addition of alpha modulation to entry guidance, the only means of controlling drag was by roll command, to keep the orbiter on a guidance-calculated reference D-V profile. One possible source of error that can cause a bias in the actual drag flown with respect to the reference drag is an IMU platform misalignment. In the presence of...

Figure Entry TRAJ drag less than drag reference

No specific crew procedures have been developed to date for the high L D case because of auto guidance capability in handling this type of L D dispersion. Although off-line runs indicate the auto guidance can make TAEM interface with 25 low L D, for variations in L D beyond this value, the miss distance at TAEM interface increases rapidly. One of the problems in monitoring the guidance for L D variations is the timely and correct interpretation of clues to a problem with L D. Low L D can be...

Figure Entry Traj drag greater than drag reference

In the CSS case illustrating the ENTRY TRAJ 1 display where drag has decreased with respect to drag reference, the indication would be as shown on figure 5-9. The (< ) is below the on the drag scale and the guidance square is ahead of the shuttle symbol. If this error were allowed to continue, the shuttle trailers would indicate the vehicle moving to the left toward the leftmost constraint boundary. In a manner similar to that described for the high drag situation, an increase in bank in this...

Use of Entry Traj Crt Displays

In this section figure 5-7 (ENTRY TRAJ 1) is used to illustrate how the information presented on the ENTRY TRAJ displays can be used for auto guidance monitoring. Because the five TRAJ displays are basically the same layout and contain the same digital readout information, the monitoring task is similar on the subsequent TRAJ displays. The health of the entry can be considered a function of (1) how well auto guidance is performing in issuing commands to keep drag on drag reference, (2) how well...

Figure Entry Traj representative display

A phugoid bank scale is displayed in the upper left corner of the display. The symbol (V) driven by roll error calculated by the entry display interface processor (DIP) is based on achieving a biased reference drag. The entry DIP calculations are completely independent with respect to the entry guidance ranging calculations. BFS stows the phugoid damper (V) until closed-loop guidance is initiated. In PASS, the phugoid damper jumps from side-to-side of the phugoid damper scale prior to guidance...

Entry CRT Parameters

Prior to beginning the discussions of each display, some mission-independent GN& C parameters common to all the entry trajectory displays should be defined. The ENTRY TRAJ 1 display, shown in figure 5-1, is representative of the common format among the entry trajectory displays. The following Gn& C parameter discussion references the ENTRY TRAJ 1 display. 1. The angle of attack currently being obtained from NAV or the ADTA subsystem operating program (SOP) is indicated by the (> )...

Entry CRT Trajectory Displays

Five entry trajectory CRT displays are available for crew monitoring of each of the four velocity phases of closed-loop entry guidance temperature control, equilibrium glide, constant drag, and transition. The information presented on range, velocity, energy-to-weight (E W) ratio, altitude rate reference, and drag reference is based on flight data obtained from the Engineering Directorate as of the last I-load update to the ENTRY TRAJ CRT displays. This information will be updated in the future...

Dedicated Displays Data Source Management

Table 5-II shows the management of the data source switches for the alpha Mach indicator (AMI), altitude vertical velocity indicator (AVVI), and the horizontal situation indicator (HSI) on the primary flight display (PFD). Table 5-II. Management of data source switches Table 5-II. Management of data source switches *CDR on DATA BUS 3, PLT on data bus 4. *CDR on DATA BUS 3, PLT on data bus 4. **During entry, the AMI and AVVI data source is either NAV or the ADS (left probe or right probe)...

Cockpit CRT Assignments

The three CRT displays on the forward panel are configured at EI as follows CRT 1 (left) - ENTRY TRAJ 1 or VERT SIT (PASS) CRT 2 (right) - GNC HORIZ SIT or OVERRIDE CRT 3 (center) - Assigned to BFS as follows - With CRT 3 Major Function switch in GNC -- ENTRY TRAJ or VERT SIT with R, P, and Y attitude errors digitally displayed for performance comparisons between PASS and BFS - With CRT 3 Major Function switch in SM -- Primary display is Thermal display. -- Depressing SYS SUMM KEY calls SM SYS...

Onboard Entry Event Reference

During entry, the events are keyed in the checklist to the best parameter for monitoring the event rather than to a common base parameter. The following parameters are used in the checklist as event cues q, EIT, EET, vrel, H, M, drag, and delta azimuth. Two clock displays are available for crew use as follows Mission timer (first line on CRT) displays mission elapsed time (00 00 00 00) from lift-off. CRT timer (second line on CRT) is set in MM 301 to count down to 00 00 00 00 at TIG, then count...

Winds

GN& C failures or degraded performance Low aft RCS propellant quantity Any of the listed conditions, if left uncorrected, could possibly lead to being unable to reach the targeted landing site or loss of vehicle control. Recognition of the off-nominal situation, as well as the ability to determine that the GN& C is performing within limits, is the primary crew task during entry. A listing of GN& C parameters monitored by the crew during entry and the cockpit display that indicates...

Section Entry Operations

5.1 CREW ENTRY MONITORING AND CONTROL Refer to the attached supplements in the appendix for discussion of the entry aerodynamics response maneuvers. The crew's primary role during entry is to monitor and control the performance of navigation, guidance, flight control, and other critical systems so that the orbiter arrives at TAEM, A L, and runway interface without violating any constraints. Cockpit dedicated instruments and CRT displays are available that present critical entry parameters for...

Omsrcs Rules Of Thumb

Below are several helpful bits of information for crewmembers and MCC to know. These data are taken from notes to an SMS Deorbit Burn training class. 1 of RCS 22 lb of propellant 1 of OMS 130 lb of propellant VGO decrements 2 fps sec for two-OMS burn 1 fps sec for one-OMS burn 0.6 fps sec for RCS burn Perigee decrements 2 fps AV 1 NM AHP Do not change items 1, 2, 3, or 4 on MNVR EXEC display during a burn Item 1, 2, or 3 - Illegal entry

Nominal Procedure

The cue card (figure 4-14) is written to use either the OMS engine on the 'good' propellant side (i.e., the side with both pods intact) or +X RCS jets. If necessary for some special reason, the other engine could be used, but this would require that procedural modifications be uplinked to the crew. Prior to the burn, a GPC read write procedure is carried out. This procedure, 'OMS SSR-1,' is found in section 11 of the 'Malfunction Procedures.' This procedure causes the proper combination of fuel...

Oms Eng Fail During Crossfeeding

At this point, both engines are being fed from the heavy pod, with the crossfeed valves open. In the event of an engine failure, the other engine continues to receive propellant. In the nominal procedures, crossfeeding is ended when the proper Y c.g. is obtained and both engines complete the burn from their own pods. However, it is not allowed to feed the one remaining engine in this case from both pods simultaneously. This could allow propellant to flow from one pod to another through the open...

Oms Prplt Fail During Crossfeeding

Since one OMS pod is feeding both OMS engines, a propellant failure may fail both OMS engines. If any propellant failure occurs above safe HP, the burn is stopped, the APU's are shut down, and the affected OMS pod is secured. Below safe HP the burn must be continued. After a propellant failure, all remaining propellant should be used for in-plane AV. The out-of-plane propellant wasting is terminated for the remainder of the burn via the ITEM 18 + 0 EXEC action. Depending on where the propellant...

Oms Prplt Fail

The OMS PRPLT FAIL section of the cue card contains procedures to follow in the event of a propellant failure. The basic cue that a propellant failure has occurred is when multiple jets fail off or AVTOT does not decrement. As in the other deorbit situations, targeting for RCS deorbit assumes that all the preburn propellant can be used, which is no longer valid after a propellant failure. Moreover, an OMS propellant failure while the +X RCS jets are burning OMS propellant may cause damage to...

Preburn

Upon entering the DEORBIT BURN cue card (figure 4-7), several checks and switch configurations are made. Since the burn can only be executed in major mode 302, the crew ensures the correct major mode. They also verify that both OMS engines are selected and that the proper trim angles are entered on the MNVR display. Flight-specific OMS engine trim values are uplinked as part of the deorbit targets. If specific numbers are not available, the crew can enter the generic numbers specified on the...

Deorbit Flight Rules

The complex deorbit burn requirements are reflected in a number of flight rules covering deorbit burn situations. Flight rules A4-152 and A4-153, contain the criteria used for deorbit burn planning and c.g. planning and for choosing off-nominal deorbit procedures if necessary. It is worth studying these rules in detail to understand the rationale behind many of the deorbit cue card procedures. A separate cue card (figures 4-5 and 4-6) containing selected deorbit flight rules is placed above the...

Deorbit Burn Events Deorbit Procedures Sequence

The sequence of deorbit events referenced to TIG or to EI is listed in table 4-I. Each event listed in the table is discussed at length in the following pages. Each page includes an event name and onboard cue, the proper crew display for monitoring the event, the crew action required, and a discussion of the event. Table 4-I. Sequence of deorbit events Table 4-I. Sequence of deorbit events SSME Hydraulic System Repressurization Hydraulic Fluid Thermal Conditioning (MCC call) Final Deorbit...

Descent Profile

The nominal descent profile is developed using an appropriate mean monthly atmosphere The mean monthly GRAM (Global Reference Atmosphere Model) atmosphere is specific to inclination and approach path geometry. The environmental model for the nominal profile simulation does not include winds. The descent profile uses standard I-load sets that are designed to accommodate the range of vehicle mass properties that may be manifested by the Shuttle Program Office. For nominal end of mission (EOM),...

Operational Constraints

Maximum aft RCS propellant consistent with mission objectives and c.g. considerations is maintained for descent control. The redline for nominal deorbit is the amount necessary to accomplish the descent and the greater of either wave-off or 1-day extension of programmed test inputs (PTI's). During atmospheric descent, the orbiter c.g. is maintained between 1075.2 and 1109 inches in the longitudinal direction and equal to or less than 1.5 inches (1.0 inch if the longitudinal c.g. is forward of...

Deorbit

When selecting the nominal deorbit revolution, the following are considered Availability of a wave-off opportunity Post-deorbit communication and tracking Entry flight test objective (FTO) phasing The deorbit maneuver is nominally targeted to achieve a steep re-entry with 3-sigma N-cycle protection. The propellant consumption during the deorbit burn is such that the propellant remaining in the OMS tank is within an acceptable tolerance for OMS tank structural limits at touchdown. The deorbit...

Figure Simplified TAEM guidance

In the lateral axis, if the guidance is in the S-turn phase, a roll angle command of 50 (30 if supersonic) is input to the FCS. If the guidance is in the acquisition phase, a roll angle command is given that is proportional to the orbiter heading deviation from tangency to the selected HAC the HAC is used for a final turn to align the orbiter to the runway. In the heading alignment phase, the roll angle command is generated to ensure that the orbiter performs a turn that follows the heading...

Transition Phase

The transition phase is based on a linear drag profile (as a function of energy) that is required to null the range errors and is used to steer the orbiter to the proper TAEM interface conditions The transition phase logic consists of a linear drag-energy profile selected by ranging requirements. Guidance software transitions to TAEM guidance when the TAEM interface criterion (relative velocity < TAEM transition velocity) is met or by crew action (keyboard entry, OPS 305 PRO). The TAEM phase...

Equilibrium Glide Phase

The equilibrium glide phase produces an equilibrium glide trajectory consistent with the ranging solution until the trajectory intersects the constant drag ( 33 ft s2) trajectory required to reach the target. The equilibrium glide phase is terminated and the constant drag phase begins when the desired constant drag level is reached. One of the alternate terminations is for the longrange case the equilibrium glide phase transfers directly to the transition phase when the predicted velocity at...

Temperature Control Phase

The temperature control phase is entered at 0.132g and is designed to control the entry trajectory, through pullout, to a temperature profile consistent with the desired total entry profile shape and the required ranging solution. The temperature control phase consists of two quadratic drag-velocity segments that are selected to minimize surface temperatures and maintain adequate dispersion margins. Range predictions are based on the two quadratic segments. The temperature control phase is...

Abbreviations And Acronyms

ACLS augmented contingency landing site ADI attitude director indicator ADTA air data transducer assembly AGL above ground level (altitude) ARCS aft reaction control system ARS atmospheric revitalization system ATCS active thermal control subsystem altitude vertical velocity indicator drag coefficient coefficient of lift rolling moment coefficient (lateral coefficient) change of rolling moment with respect to the change in sideslip angle pitching moment coefficient (longitudinal coefficient)...

Tables

3-I Dynamic pressure 4-I Sequence of deorbit 5-I Entry GN& C flight monitoring 5-II Management of data source 5-III Summary of entry events 5-IV ADS parameters used by 5-V Air data moding and 5-VI Display data 5-VII HSI output information in TAEM and A L 2-1 Simplified entry 2-2 Typical entry corridor and reference profile versus range and 2-3 Guidance for nominal 2-4 Typical TAEM energy-to-weight 2-5 Simplified TAEM 2-6 TAEM guidance phase and ground track 2-7 A L longitudinal 2-8...

Preentry Phase

The pre-entry phase is an attitude hold mode before atmospheric entry and is an open-loop phase ending at 0.132g (4.25 ft s2). Vehicle attitude is maintained by aft RCS jets to hold a constant bank (usually 0 ) and 40 angle of attack through EI. At 0.132g, pre-entry is terminated and the temperature control phase begins. For the extremely short-range case, pre-entry will be terminated and the constant drag phase will begin, if the current constant drag level to reach the target is greater than...

Frcs Completion

* MNVR to -X Att (pitch up at 3 deg sec to VGOz +1 4 AVTOT) * * THC -X to TGT HP or FRCS depletion (JETS FAIL OFF) * When the crew has used all the available OMS propellant and reconfigured for aft RCS jets, the next step in completing the burn is to use aft RCS propellant (THC +X) until the burn target is achieved (CUR HP TGT HP) or until the aft RCS propellant is reduced to TOT AFT QTY 1. The RCS quantities can be read on the BFS SYS SUMM 2 display and on the quantity gauges on panel O3 if...

Ei C Secondary Actuator Check

(if not previously performed and time permits) If port does not bypass during check, bypass affected port after check SEC ACT BYPASS - ITEM 8 +X X EXEC If affected port still does not bypass R2 1. HYD MN PUMP PRESS (one) - NORM CRT3 2. SURF DRIVE ON, ITEM 39 EXEC (*) Wait at least 5 sec MDU VSPI Stop drive test when elevon posns within +12 to -27 SURF DRIVE OFF, ITEM 40 EXEC (*) CRT1 3. VPOS STIM ENA, ITEM 7 - (no *) CRT1 5. SEC ACT CK, CH 1 - ITEM 1 EXEC (*) C3 7. FCS CH 1 - ORIDE CRT1 VAll CH...

Figure Phugoid damper plot

The D-BASE term is a function of relative velocity and is determined by one of the three linear equations in figure 5-10. The D-BASE term is used in the determination of the DREF value digitally displayed under the bias item 1 on the ENTRY TRAJ displays. With a bias of zero, the D-BASE is the DREF for the phugoid damper, where DREF is defined as DREF D-BASE + bias item. The bias item allows shifting of the drag value obtained from the linear drag versus velocity profile. The item entry accepts...

Acknowledgment

Major contributions to the Entry Flight Procedures Handbook were made by the following individuals Gene Bell Ken Patterson Holly Barnes Mason Lancaster William O'Keefe Jennifer Kreykes John Shannon Drum Simpson Mark Sims Glen Hillier Cori Kerr William Powers 1.3 ABBREVIATIONS AND 1.4 SIGNS AND 2 ENTRY FLIGHT 2.2 DEORBIT BURN 2.3 ENTRY INTERFACE TO TERMINAL AREA ENERGY MANAGEMENT 2-2 2.3.1 Preentry 2.3.2 Temperature Control 2.3.3 Equilibrium Glide Phase 2-5 2.3.4 Constant Drag 2.3.5 Transition...

Deorbit Burn Overview

Following seat ingress activities, the commander CDR and pilot PLT copy updates to the deorbit, entry, and landing DEL preliminary advisory data PAD and the orbital maneuvering system OMS propellant PRPLT PAD. The CDR checks and loads the final deorbit targets previously uplinked by the Mission Control Center MCC . During the remaining half hour before deorbit ignition, the crew configures the horizontal situation display HSD , checks the switch positions for an OMS or reaction control system...

Figure Gps Status display PFS

The Global Positioning System GPS STATUS display SPEC 55 provides the crew with the capability to monitor and control GPS operations. It is available throughout OPS 3, as well as OPS 2, 8, and 9. Information associated with uninstalled receivers is blanked or NI not installed displayed. For single string flights, only GPS 2 data is active. Execution of item entries for uninstalled units results in 'ILLEGAL ENTRY'. The upper portion of the display contains status and performance information. The...

Phugoid Damper

The phugoid damper was incorporated as part of the TRAJ displays to give the crew a 'fly-to' bank angle calculated to avoid phugoid instability and help the crew to control the entry drag range problem while flying in the CSS mode. The logic for the phugoid damper is contained in the entry DIP. Three linear segmented lines define a drag versus velocity profile the associated values that define this profile are I-loaded constants figure 5-10 .

Taem

For each of the phases listed, this handbook includes a nominal sequence of trajectory and system events and the interrelationship of the crew and the orbiter entry systems for flying and monitoring the event. Approach and landing A L to rollout and post-landing phases are not covered in this handbook. The Approach Landing Flight Procedures Handbook JSC-23266 provides detailed information on these final flight phases. It is assumed that the crewmember is already knowledgeable about shuttle...

Vertical Situation Displays

Two Vertical Situation Displays VSD are used to monitor the guidance function in the TAEM region. The VERT SIT 1 display comes up automatically at TAEM interface or when the crew performs an OPS 305 PRO or an OPS 602 PRO. It also comes up automatically at the end of the Z-translation maneuver in the case of a return to launch site RTLS abort. This discussion does not address the use of these displays as applied to an RTLS and the reader is referred to the Ascent Abort Flight Procedures...

Assumptions Guidelines And Constraints

All design assumptions, guidelines and constraints applicable to the entry phase are defined in NSTS 21075, Space Shuttle Operational Flight Design Standard Groundrules and Constraints -Level B. The Level B GR amp C references several other controlling documents for additional constraints, including NSTS 07700, Space Shuttle Program Definition and Requirements -Volumes III and X, and NSTS 08934, Shuttle Operational Data Book - Vol V. All operational constraints applicable to entry are defined...

Figure Deorbit Burn RCS cue card

THC X to TGT HP or TOT AFT QTY 1 THC X to PREBANK FLIP HP or TOT AFT QTY 2 MNVR to -X Att pitch up at 3 sec to VGOz 1 4 aVTOT THC -X to TGT HP or FRCS depletion JETS FAIL OFF CUTOFF VGOx 0, release THC AFT RCS RECONFIG Trim Inplane X,Z residuals lt 2 fps lt 0.5 fps if shallow Once the crew has loaded the deorbit burn target on the DEORB MNVR display for the RCS SEL X RCS option, they will maneuver to the inertial burn attitude that has been calculated. Venting can cause the orbiter to wallow...

Use of Phugoid Damper

Although CSS entries are not currently planned and the probability of having to perform one is low, an emergency deorbit using the phugoid damper is possible, in the event of certain severe combinations of malfunctions. At a drag equal to 3 ft s2 or q equal to approximately 8 lb ft2, the logic for the phugoid damper is initiated. The crew can detect this by the appearance of a roll error bug command on the BFS TRAJ 1 phugoid bank scale and by the appearance of the guidance symbol in PASS TRAJ...

Unbalanced Prplt Deorbit Burn

This is the longest deorbit cue card figure 4-11 and is used when one OMS pod is significantly heavier than the other. The procedure is designed to balance the Y c.g. by burning more OMS propellant on the heavy side. The burn is started with the propellant from the heavy side feeding both OMS engines. The crew will return to straight feed during the burn when the Y c.g. is balanced. The burn is then completed in the normal configuration. This is not considered an off-nominal procedure because...