# L38 Pre-flight **Block 4: Aircraft Survivability and Mission Planning — Lesson 38: Final Project Work Day** *Work this before L38. Pre-flights are never collected — in class, anyone may be cold-called to present any question at the board, and that recitation is the participation grade.* --- ## Assumed pre-class reading - The Final Project handout — its Models (aspect, detection contour, route planning), its Use of AI section and the appendix of sample AI prompts, and its Sources and The Paper sections. - The L32 and L34 readings: the aspect a radar sees, the $R^4$ contour, and why an aspect-aware route graph is directed. - The L38 page — the template, the AI rules for the paper, and how to cite course lessons. This quiz ties the route to the paper: the first three questions follow one heading through Blocks 1, 3 and 4, and the last two are the paper's rules for citing the course and for using AI. --- ## Quiz questions (5 items, ~5 minutes) **Q1.** (Multiple choice) An X-band SAM radar sits at the origin. A B-21 is 50 km due east of it (bearing φ = 090° from the radar), on a grid edge that runs east–west. The radar detects the B-21 **nose-on** out to 48 km; the X-band pattern reads −15 dBsm nose-on, −3 dBsm at the beam and −10 dBsm tail-on. With θ = wrap(φ + 180° − ψ), which aspect does the radar see on each heading, and is the B-21 detected at 50 km? - [ ] (a) Westbound nose-on, R = 48 km: not detected. Eastbound tail-on, R ≈ 64 km: detected. - [ ] (b) Westbound tail-on, R ≈ 64 km: detected. Eastbound nose-on, R = 48 km: not detected. - [ ] (c) Both headings beam-on, R ≈ 96 km: detected either way, since the radar sees the same side. - [ ] (d) Westbound nose-on, R = 48 km: not detected. Eastbound tail-on, R ≈ 85 km: detected. --- **Q2.** (Multiple choice) An aspect-aware planner stores the leg from grid node a to node b and the leg from b back to a as two separate edges, with different costs, although both cover the same stretch of ground. Why? - [ ] (a) Dijkstra's algorithm runs only on a directed graph, so MATLAB's `shortestpath` needs each leg stored twice. - [ ] (b) An edge's cost includes the cost already paid to reach its first node, and that differs at a and at b. - [ ] (c) Reversing the leg reverses the heading, so each radar sees another aspect, σ and contour, and another lethal length. - [ ] (d) The aircraft burns more fuel on one of the two, because it flies the ingress heavier than it flies the egress. --- **Q3.** (Multiple choice) T3 also asks for an **aspect-blind** plan, which prices every edge with the B-21's nose-on signature. With the X-band pattern of Q1 (and about −28 dBsm near 45° off the nose), which statement is true? - [ ] (a) It is conservative, because nose-on is the largest X-band RCS, so every aspect-aware contour lies inside it. - [ ] (b) It still needs a digraph, because "nose-on" is defined from the heading, and reversing an edge flips it. - [ ] (c) It gives the true $P_S$ of its own route, since each of that route's edges was scored when it was planned. - [ ] (d) Each edge costs the same both ways; its route's true $P_S$ comes only from re-scoring it aspect-aware. --- **Q4.** (Multiple choice) Four drafts cite course lessons as listed below. Which one meets the Final Project's citation rule? - [ ] (a) L31, L32, L34 and L36, each cited in the sentence whose specific claim it supports - [ ] (b) L3, L14, L25 and L34, each cited in the sentence whose specific claim it supports - [ ] (c) L3, L14 and L25, each cited for its claim, plus a peer-reviewed journal article on routing - [ ] (d) L3, L14, L25 and L34, cited once together: "this work builds on [1]–[4]" --- **Q5.** (Short answer) You have worked out your T3 approach on paper: loop over the grid's edges, take each edge's heading, find the aspect each radar sees, and sum λℓ into that edge's weight in a `digraph`. (i) May you ask an AI to turn that approach into MATLAB that calls `FPToolkit.m`? Under what conditions? (ii) Name one request about the *paper* that the policy allows and one it forbids. (iii) If you used AI at all, what must you submit, and with what?