diff --git a/src/aircraft_details.cpp b/src/aircraft_details.cpp
index c693c8d..76b3585 100644
--- a/src/aircraft_details.cpp
+++ b/src/aircraft_details.cpp
@@ -1,4 +1,7 @@
 #include "aircraft_details.h"
+#include "sd_storage.h"
+#include "config.h"
+#include <SD.h>
 #include <WiFiClientSecure.h>
 #include <HTTPClient.h>
 #include <ArduinoJson.h>
@@ -11,19 +14,24 @@ namespace AircraftDetails {
 namespace {
     SemaphoreHandle_t mutex = nullptr;
 
-    char pendingHex[7] = {0};
-    char pendingCallsign[9] = {0};
-    bool hasPending = false;
-
-    constexpr uint8_t CACHE_SIZE = 4;
-    struct CacheEntry {
+    constexpr uint8_t RING_SIZE = 8;
+    struct RingEntry {
         char hex[7] = {0};
         Info info;
     };
-    CacheEntry cache[CACHE_SIZE];
-    uint8_t nextCacheSlot = 0;
+    RingEntry ring[RING_SIZE];
+    uint8_t ringNext = 0;
+
+    char pendingHex[7] = {0};
+    char pendingCallsign[9] = {0};
+
+    enum class Phase { Idle, ModelSrc1, ModelSrc2, RouteSrc1, RouteSrc2, RouteSrc3, Done };
+    Phase currentPhase = Phase::Idle;
+
+    char workHex[7] = {0};
+    char workCallsign[9] = {0};
+    Info workResult;
 
-    // Persistent client — avoids repeated TLS handshakes (~0.5-1s each).
     WiFiClientSecure persistentClient;
     bool clientConfigured = false;
 
@@ -31,6 +39,23 @@ namespace {
         if (mutex == nullptr) mutex = xSemaphoreCreateMutex();
     }
 
+    int ringFind(const char* hex) {
+        for (uint8_t i = 0; i < RING_SIZE; i++) {
+            if (strcmp(ring[i].hex, hex) == 0) return i;
+        }
+        return -1;
+    }
+
+    void ringStore(const char* hex, const Info& info) {
+        int slot = ringFind(hex);
+        if (slot < 0) {
+            slot = ringNext;
+            ringNext = (ringNext + 1) % RING_SIZE;
+        }
+        strncpy(ring[slot].hex, hex, sizeof(ring[slot].hex) - 1);
+        ring[slot].info = info;
+    }
+
     bool httpGetString(const String& url, String& outBody, uint32_t timeoutMs) {
         if (!clientConfigured) {
             persistentClient.setInsecure();
@@ -49,31 +74,148 @@ namespace {
         return ok;
     }
 
-    int findCacheSlot(const char* hex) {
-        for (uint8_t i = 0; i < CACHE_SIZE; i++) {
-            if (strcmp(cache[i].hex, hex) == 0) return i;
+    bool loadFromSd(const char* hex, Info& out) {
+        if (!SdStorage::isMounted()) return false;
+        String path = String(Config::SD_DETAIL_CACHE_DIR) + "/" + hex + ".txt";
+        File f = SD.open(path);
+        if (!f) return false;
+        char line[64];
+        while (f.available()) {
+            int len = f.readBytesUntil('\n', line, sizeof(line) - 1);
+            line[len] = '\0';
+            char* eq = strchr(line, '=');
+            if (!eq) continue;
+            *eq = '\0';
+            const char* val = eq + 1;
+            if (strcmp(line, "model") == 0) {
+                strncpy(out.model, val, sizeof(out.model) - 1);
+            } else if (strcmp(line, "route") == 0) {
+                char* dash = strchr(val, '-');
+                if (dash) {
+                    *dash = '\0';
+                    strncpy(out.routeOrigin, val, sizeof(out.routeOrigin) - 1);
+                    strncpy(out.routeDest, dash + 1, sizeof(out.routeDest) - 1);
+                }
+            }
         }
-        return -1;
+        f.close();
+        return out.model[0] || out.routeOrigin[0];
     }
 
-    void storeInCache(const char* hex, const Info& info) {
-        int slot = findCacheSlot(hex);
-        if (slot < 0) {
-            slot = nextCacheSlot;
-            nextCacheSlot = (nextCacheSlot + 1) % CACHE_SIZE;
+    void saveToSd(const char* hex, const Info& info) {
+        if (!SdStorage::isMounted()) return;
+        SD.mkdir(Config::SD_DETAIL_CACHE_DIR);
+        String path = String(Config::SD_DETAIL_CACHE_DIR) + "/" + hex + ".txt";
+        File f = SD.open(path, FILE_WRITE);
+        if (!f) return;
+        f.print("model="); f.println(info.model);
+        f.print("route=");
+        if (info.routeOrigin[0]) { f.print(info.routeOrigin); f.print("-"); f.println(info.routeDest); }
+        else { f.println(); }
+        f.close();
+    }
+
+    void applyRouteCodes(const String& codes) {
+        int dash = codes.indexOf('-');
+        if (dash > 0 && dash < (int)codes.length() - 1) {
+            strncpy(workResult.routeOrigin, codes.substring(0, dash).c_str(), sizeof(workResult.routeOrigin) - 1);
+            strncpy(workResult.routeDest, codes.substring(dash + 1).c_str(), sizeof(workResult.routeDest) - 1);
+        }
+    }
+
+    bool advance() {
+        switch (currentPhase) {
+            case Phase::ModelSrc1: {
+                String body;
+                if (httpGetString(String("https://hexdb.io/api/v1/aircraft/") + workHex, body, 2000)) {
+                    JsonDocument doc;
+                    if (!deserializeJson(doc, body)) {
+                        const char* m = doc["Manufacturer"] | "";
+                        const char* t = doc["Type"] | "";
+                        if (m[0] && t[0]) snprintf(workResult.model, sizeof(workResult.model), "%s %s", m, t);
+                        else if (t[0]) strncpy(workResult.model, t, sizeof(workResult.model) - 1);
+                    }
+                }
+                currentPhase = workResult.model[0] ? Phase::RouteSrc1 : Phase::ModelSrc2;
+                return true;
+            }
+            case Phase::ModelSrc2: {
+                String body;
+                if (httpGetString(String("https://api.adsbdb.com/v0/aircraft/") + workHex, body, 2000)) {
+                    JsonDocument doc;
+                    if (!deserializeJson(doc, body)) {
+                        const char* m = doc["response"]["aircraft"]["manufacturer"] | "";
+                        const char* t = doc["response"]["aircraft"]["type"] | "";
+                        if (m[0] && t[0]) snprintf(workResult.model, sizeof(workResult.model), "%s %s", m, t);
+                        else if (t[0]) strncpy(workResult.model, t, sizeof(workResult.model) - 1);
+                    }
+                }
+                currentPhase = Phase::RouteSrc1;
+                return true;
+            }
+            case Phase::RouteSrc1: {
+                String cs = String(workCallsign);
+                cs.trim(); cs.toUpperCase();
+                if (cs.length() >= 2) {
+                    String body;
+                    String folder = cs.substring(0, 2);
+                    if (httpGetString(String("https://vrs-standing-data.adsb.lol/routes/") + folder + "/" + cs + ".json", body, 2000)) {
+                        JsonDocument doc;
+                        if (!deserializeJson(doc, body)) {
+                            applyRouteCodes(String(doc["airport_codes"] | ""));
+                        }
+                    }
+                }
+                currentPhase = workResult.routeOrigin[0] ? Phase::Done : Phase::RouteSrc2;
+                return true;
+            }
+            case Phase::RouteSrc2: {
+                String cs = String(workCallsign);
+                cs.trim(); cs.toUpperCase();
+                if (cs.length() >= 2) {
+                    String body;
+                    if (httpGetString(String("https://hexdb.io/api/v1/route/icao/") + cs, body, 2000)) {
+                        JsonDocument doc;
+                        if (!deserializeJson(doc, body)) {
+                            applyRouteCodes(String(doc["route"] | ""));
+                        }
+                    }
+                }
+                currentPhase = workResult.routeOrigin[0] ? Phase::Done : Phase::RouteSrc3;
+                return true;
+            }
+            case Phase::RouteSrc3: {
+                String cs = String(workCallsign);
+                cs.trim(); cs.toUpperCase();
+                if (cs.length() > 0) {
+                    String body;
+                    if (httpGetString(String("https://api.adsbdb.com/v0/callsign/") + cs, body, 2000)) {
+                        JsonDocument doc;
+                        if (!deserializeJson(doc, body)) {
+                            const char* o = doc["response"]["flightroute"]["origin"]["icao_code"] | "";
+                            const char* d = doc["response"]["flightroute"]["destination"]["icao_code"] | "";
+                            if (o[0] && d[0]) {
+                                strncpy(workResult.routeOrigin, o, sizeof(workResult.routeOrigin) - 1);
+                                strncpy(workResult.routeDest, d, sizeof(workResult.routeDest) - 1);
+                            }
+                        }
+                    }
+                }
+                currentPhase = Phase::Done;
+                return true;
+            }
+            default:
+                return false;
         }
-        strncpy(cache[slot].hex, hex, sizeof(cache[slot].hex) - 1);
-        cache[slot].info = info;
     }
 }
 
 void request(const char* hex, const char* callsign) {
     ensureMutex();
     xSemaphoreTake(mutex, portMAX_DELAY);
-    if (findCacheSlot(hex) < 0 && strcmp(pendingHex, hex) != 0) {
+    if (currentPhase == Phase::Idle && ringFind(hex) < 0 && strcmp(pendingHex, hex) != 0) {
         strncpy(pendingHex, hex, sizeof(pendingHex) - 1);
         strncpy(pendingCallsign, callsign ? callsign : "", sizeof(pendingCallsign) - 1);
-        hasPending = true;
     }
     xSemaphoreGive(mutex);
 }
@@ -82,11 +224,17 @@ Info get(const char* hex) {
     ensureMutex();
     xSemaphoreTake(mutex, portMAX_DELAY);
     Info out;
-    int slot = findCacheSlot(hex);
+    int slot = ringFind(hex);
     if (slot >= 0) {
-        out = cache[slot].info;
-    } else if (strcmp(pendingHex, hex) == 0 && hasPending) {
+        out = ring[slot].info;
+    } else if (currentPhase != Phase::Idle && strcmp(workHex, hex) == 0) {
         out.loading = true;
+        // Return partial results as they arrive
+        if (workResult.model[0]) strncpy(out.model, workResult.model, sizeof(out.model) - 1);
+        if (workResult.routeOrigin[0]) {
+            strncpy(out.routeOrigin, workResult.routeOrigin, sizeof(out.routeOrigin) - 1);
+            strncpy(out.routeDest, workResult.routeDest, sizeof(out.routeDest) - 1);
+        }
     }
     xSemaphoreGive(mutex);
     return out;
@@ -94,111 +242,42 @@ Info get(const char* hex) {
 
 void update() {
     ensureMutex();
-
-    char hex[7] = {0};
-    char callsign[9] = {0};
-    bool doWork = false;
-
     xSemaphoreTake(mutex, portMAX_DELAY);
-    if (hasPending) {
-        strncpy(hex, pendingHex, sizeof(hex) - 1);
-        strncpy(callsign, pendingCallsign, sizeof(callsign) - 1);
-        doWork = true;
-    }
-    xSemaphoreGive(mutex);
 
-    if (!doWork) return;
-
-    Info result;
-
-    // Model lookup — try hexdb.io first, fallback to adsbdb.com.
-    // Timeout reduced to 2s per source (was 3-4s) since we chain fallbacks.
-    String body;
-    if (httpGetString(String("https://hexdb.io/api/v1/aircraft/") + hex, body, 2000)) {
-        JsonDocument doc;
-        DeserializationError err = deserializeJson(doc, body);
-        if (!err) {
-            const char* manufacturer = doc["Manufacturer"] | "";
-            const char* type = doc["Type"] | "";
-            if (manufacturer[0] && type[0]) {
-                snprintf(result.model, sizeof(result.model), "%s %s", manufacturer, type);
-            } else if (type[0]) {
-                strncpy(result.model, type, sizeof(result.model) - 1);
+    if (currentPhase == Phase::Idle) {
+        if (pendingHex[0]) {
+            // Check SD cache before doing network
+            Info cached;
+            if (loadFromSd(pendingHex, cached)) {
+                ringStore(pendingHex, cached);
+                memset(pendingHex, 0, sizeof(pendingHex));
+                memset(pendingCallsign, 0, sizeof(pendingCallsign));
+                xSemaphoreGive(mutex);
+                return;
             }
+            strncpy(workHex, pendingHex, sizeof(workHex) - 1);
+            strncpy(workCallsign, pendingCallsign, sizeof(workCallsign) - 1);
+            workResult = Info{};
+            memset(pendingHex, 0, sizeof(pendingHex));
+            memset(pendingCallsign, 0, sizeof(pendingCallsign));
+            currentPhase = Phase::ModelSrc1;
         }
     }
 
-    if (!result.model[0]) {
-        String body2;
-        if (httpGetString(String("https://api.adsbdb.com/v0/aircraft/") + hex, body2, 2000)) {
-            JsonDocument doc2;
-            DeserializationError err2 = deserializeJson(doc2, body2);
-            if (!err2) {
-                const char* manufacturer = doc2["response"]["aircraft"]["manufacturer"] | "";
-                const char* type = doc2["response"]["aircraft"]["type"] | "";
-                if (manufacturer[0] && type[0]) {
-                    snprintf(result.model, sizeof(result.model), "%s %s", manufacturer, type);
-                } else if (type[0]) {
-                    strncpy(result.model, type, sizeof(result.model) - 1);
-                }
-            }
-        }
+    if (currentPhase == Phase::Idle) {
+        xSemaphoreGive(mutex);
+        return;
     }
 
-    // Route lookup — via chain of three sources, 2s timeout each.
-    String trimmedCallsign = String(callsign);
-    trimmedCallsign.trim();
-    trimmedCallsign.toUpperCase();
+    // Do one HTTP request, then return
+    bool working = advance();
 
-    auto applyRouteCodes = [&](const String& codes) {
-        int dash = codes.indexOf('-');
-        if (dash > 0 && dash < (int)codes.length() - 1) {
-            strncpy(result.routeOrigin, codes.substring(0, dash).c_str(), sizeof(result.routeOrigin) - 1);
-            strncpy(result.routeDest, codes.substring(dash + 1).c_str(), sizeof(result.routeDest) - 1);
-        }
-    };
-
-    if (trimmedCallsign.length() >= 2) {
-        String body3;
-        String folder = trimmedCallsign.substring(0, 2);
-        if (httpGetString(String("https://vrs-standing-data.adsb.lol/routes/") + folder + "/" + trimmedCallsign + ".json", body3, 2000)) {
-            JsonDocument doc3;
-            if (!deserializeJson(doc3, body3)) {
-                const char* codes = doc3["airport_codes"] | "";
-                applyRouteCodes(String(codes));
-            }
-        }
-
-        if (!result.routeOrigin[0] || !result.routeDest[0]) {
-            String body4;
-            if (httpGetString(String("https://hexdb.io/api/v1/route/icao/") + trimmedCallsign, body4, 2000)) {
-                JsonDocument doc4;
-                if (!deserializeJson(doc4, body4)) {
-                    const char* route = doc4["route"] | "";
-                    applyRouteCodes(String(route));
-                }
-            }
-        }
+    if (!working || currentPhase == Phase::Done) {
+        saveToSd(workHex, workResult);
+        ringStore(workHex, workResult);
+        currentPhase = Phase::Idle;
     }
 
-    if (trimmedCallsign.length() > 0 && (!result.routeOrigin[0] || !result.routeDest[0])) {
-        String body5;
-        if (httpGetString(String("https://api.adsbdb.com/v0/callsign/") + trimmedCallsign, body5, 2000)) {
-            JsonDocument doc5;
-            if (!deserializeJson(doc5, body5)) {
-                const char* originIcao = doc5["response"]["flightroute"]["origin"]["icao_code"] | "";
-                const char* destIcao = doc5["response"]["flightroute"]["destination"]["icao_code"] | "";
-                if (originIcao[0] && destIcao[0]) {
-                    strncpy(result.routeOrigin, originIcao, sizeof(result.routeOrigin) - 1);
-                    strncpy(result.routeDest, destIcao, sizeof(result.routeDest) - 1);
-                }
-            }
-        }
-    }
-
-    xSemaphoreTake(mutex, portMAX_DELAY);
-    storeInCache(hex, result);
-    hasPending = false;
     xSemaphoreGive(mutex);
 }
 
diff --git a/src/aircraft_details.h b/src/aircraft_details.h
index 00655a6..01ccd8f 100644
--- a/src/aircraft_details.h
+++ b/src/aircraft_details.h
@@ -1,10 +1,13 @@
 #pragma once
 #include <Arduino.h>
 
-// Additional aircraft details (model) that are NOT part of the ADS-B signal
-// and get looked up via the free hexdb.io community database by hex code -
-// only for the currently selected aircraft (not for all of them, to keep
-// network load low).
+// Additional aircraft details (model + route) that are NOT part of
+// the ADS-B signal and get looked up via a chain of free community
+// databases (hexdb.io, adsbdb.com, adsb.lol) by hex code and callsign.
+// Results are cached on the SD card (/Flightradar_cyd/cache/{hex}.txt)
+// so each aircraft only needs to be fetched once, ever.
+// Lookups are spread across multiple update() calls (state machine,
+// one HTTP request per call) so Core 0 is never blocked for long.
 namespace AircraftDetails {
 
     struct Info {
diff --git a/src/config.h b/src/config.h
index e42adad..3247c03 100644
--- a/src/config.h
+++ b/src/config.h
@@ -85,6 +85,7 @@ constexpr float RANGE_STEPS_KM[] = {10.0f, 25.0f, 50.0f, 100.0f};
     constexpr const char* SD_SETTINGS_FILE         = "/Flightradar_cyd/config.txt";
     constexpr const char* SD_WIFI_CREDENTIALS_FILE = "/Flightradar_cyd/wifi.txt";
     constexpr const char* SD_CALIBRATION_FILE      = "/Flightradar_cyd/calibration.txt";
+constexpr const char* SD_DETAIL_CACHE_DIR       = "/Flightradar_cyd/cache";
 
     constexpr uint8_t SD_SPI_CS_PIN   = 5;
     constexpr uint8_t SD_SPI_MOSI_PIN = 23;
diff --git a/src/ota_update.cpp b/src/ota_update.cpp
index 8dec2a7..98e7743 100644
--- a/src/ota_update.cpp
+++ b/src/ota_update.cpp
@@ -92,24 +92,15 @@ CheckInfo checkForUpdate() {
     strncpy(info.latestVersion, (tag[0] == 'v' || tag[0] == 'V') ? tag + 1 : tag,
             sizeof(info.latestVersion) - 1);
 
-    // Use browser_download_url from the API response — this contains the
-    // external proxy URL (https://git.rasmusbendtsen.dk/...) which the
-    // ESP32 can reach through the proxy.
-    JsonArray assets = doc["assets"];
-    for (JsonObject asset : assets) {
-        const char* name = asset["name"] | "";
-        if (strcmp(name, "firmware.bin") == 0) {
-            const char* dlUrl = asset["browser_download_url"] | "";
-            strncpy(info.downloadUrl, dlUrl, sizeof(info.downloadUrl) - 1);
-            break;
-        }
-    }
+    // Construct download URL from the tag name using Gitea's standard
+    // release asset pattern. browser_download_url from the API contains
+    // the internal IP (http://192.168.0.37:3000/...) which the ESP32
+    // cannot use — it needs the external proxy URL.
+    String dlUrl = String("https://git.rasmusbendtsen.dk/rasmus/flyradar/releases/download/")
+                 + String(tag) + "/firmware.bin";
+    strncpy(info.downloadUrl, dlUrl.c_str(), sizeof(info.downloadUrl) - 1);
 
-    if (!info.downloadUrl[0]) {
-        Serial.printf("[OTA] Check failed: Release v%s has no firmware.bin attachment.\n",
-                      info.latestVersion);
-        return info;
-    }
+    Serial.printf("[OTA] Download URL: %s\n", info.downloadUrl);
 
     int cmp = compareVersions(info.latestVersion, Config::APP_VERSION);
     info.result = (cmp > 0) ? CheckResult::UpdateAvailable : CheckResult::UpToDate;