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What makes the Xplorer such a popular F3J model?

Written by Gordon Buckland. Extended Digital Content from the March 2013 RC Soaring Column. Also featured in the March 2013 Model Aviation tablet app. The Xplorer F3J model, produced by NAN Models in Bulgaria, is considered to be the most popular molded F3J/Thermal Duration model in the world since its introduction to the US market in mid-2008. The Xplorer had success in 2007 in the hands of European pilots, including Benedikt Feigl, who won the F3J World Championship in 2008 with a v-tail version. The model has evolved because the original D-box iterations were slightly fragile…

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( ! ) Fatal error: Uncaught TypeError: Drupal\Core\Database\StatementWrapperIterator::__construct(): Argument #2 ($clientConnection) must be of type object, null given, called in /var/www/html/web/core/lib/Drupal/Core/Database/Connection.php on line 441 and defined in /var/www/html/web/core/lib/Drupal/Core/Database/StatementWrapperIterator.php on line 38
( ! ) TypeError: Drupal\Core\Database\StatementWrapperIterator::__construct(): Argument #2 ($clientConnection) must be of type object, null given, called in /var/www/html/web/core/lib/Drupal/Core/Database/Connection.php on line 441 in /var/www/html/web/core/lib/Drupal/Core/Database/StatementWrapperIterator.php on line 38
Call Stack
#TimeMemoryFunctionLocation
14.248626658416_drupal_exception_handler( $exception = class TypeError { protected $message = 'Drupal\\Core\\Database\\StatementWrapperIterator::__construct(): Argument #2 ($clientConnection) must be of type object, null given, called in /var/www/html/web/core/lib/Drupal/Core/Database/Connection.php on line 441'; private string ${Error}string = ''; protected $code = 0; protected string $file = '/var/www/html/web/core/lib/Drupal/Core/Database/StatementWrapperIterator.php'; protected int $line = 38; private array ${Error}trace = [0 => [...], 1 => [...], 2 => [...], 3 => [...], 4 => [...], 5 => [...], 6 => [...], 7 => [...], 8 => [...], 9 => [...], 10 => [...]]; private ?Throwable ${Error}previous = NULL } ).../bootstrap.inc:0
24.249826579040_drupal_exception_handler_additional( $exception = class TypeError { protected $message = 'Drupal\\Core\\Database\\StatementWrapperIterator::__construct(): Argument #2 ($clientConnection) must be of type object, null given, called in /var/www/html/web/core/lib/Drupal/Core/Database/Connection.php on line 441'; private string ${Error}string = ''; protected $code = 0; protected string $file = '/var/www/html/web/core/lib/Drupal/Core/Database/StatementWrapperIterator.php'; protected int $line = 38; private array ${Error}trace = [0 => [...], 1 => [...], 2 => [...], 3 => [...], 4 => [...], 5 => [...], 6 => [...], 7 => [...], 8 => [...], 9 => [...], 10 => [...]]; private ?Throwable ${Error}previous = NULL }, $exception2 = class TypeError { protected $message = 'Drupal\\Core\\Database\\StatementWrapperIterator::__construct(): Argument #2 ($clientConnection) must be of type object, null given, called in /var/www/html/web/core/lib/Drupal/Core/Database/Connection.php on line 441'; private string ${Error}string = ''; protected $code = 0; protected string $file = '/var/www/html/web/core/lib/Drupal/Core/Database/StatementWrapperIterator.php'; protected int $line = 38; private array ${Error}trace = [0 => [...], 1 => [...], 2 => [...], 3 => [...], 4 => [...], 5 => [...], 6 => [...], 7 => [...], 8 => [...], 9 => [...], 10 => [...], 11 => [...], 12 => [...]]; private ?Throwable ${Error}previous = NULL } ).../bootstrap.inc:126
34.249826579040error_displayable( $error = ??? ).../bootstrap.inc:142
44.249826579040_drupal_get_error_level( ).../errors.inc:118
54.249826579040Drupal::config( $name = 'system.logging' ).../errors.inc:331
64.249826579040Drupal\Core\Config\ConfigFactory->get( $name = 'system.logging' ).../Drupal.php:421
74.249826579040Drupal\Core\Config\ConfigFactory->doGet( $name = 'system.logging', $immutable = ??? ).../ConfigFactory.php:89
84.249826579256Drupal\Core\Config\ConfigFactory->doLoadMultiple( $names = [0 => 'system.logging'], $immutable = TRUE ).../ConfigFactory.php:104
94.249826579368Drupal\Core\Config\CachedStorage->readMultiple( $names = [0 => 'system.logging'] ).../ConfigFactory.php:165
104.249826579992Drupal\Core\Cache\DatabaseBackend->getMultiple( $cids = [0 => 'system.logging'], $allow_invalid = ??? ).../CachedStorage.php:87
114.249926581152Drupal\Core\Database\Connection->query( $query = 'SELECT [cid], [data], [created], [expire], [serialized], [tags], [checksum] FROM {cache_config} WHERE [cid] IN ( :cids[] ) ORDER BY [cid]', $args = [':cids[]' => [0 => 'system.logging']], $options = ??? ).../DatabaseBackend.php:131
124.249926582200Drupal\Core\Database\Connection->prepareStatement( $query = 'SELECT [cid], [data], [created], [expire], [serialized], [tags], [checksum] FROM {cache_config} WHERE [cid] IN ( :cids__0 ) ORDER BY [cid]', $options = ['fetch' => enum Drupal\Core\Database\Statement\FetchAs::Object, 'allow_delimiter_in_query' => FALSE, 'allow_square_brackets' => FALSE, 'pdo' => []], $allow_row_count = ??? ).../Connection.php:664
134.249926582712Drupal\Core\Database\StatementWrapperIterator->__construct( $connection = class Drupal\mysql\Driver\Database\mysql\Connection { protected $target = 'default'; protected $key = 'default'; protected $logger = NULL; protected $driverClasses = ['PagerSelectExtender' => 'PagerSelectExtender']; protected $statementWrapperClass = 'Drupal\\Core\\Database\\StatementWrapperIterator'; protected $transactionalDDLSupport = FALSE; protected $connection = NULL; protected $connectionOptions = ['database' => 'dpl_jsvvhikdao', 'username' => 'vdmompnaig', 'password' => 'jC21cXfOuRnJw5HFKE', 'host' => 'devpanel-cluster-agebjmjp-aurora-cluster.cluster-coyf2dezrpfe.us-east-2.rds.amazonaws.com', 'port' => '3306', 'driver' => 'mysql', 'prefix' => '', 'collation' => 'utf8mb4_general_ci', 'namespace' => 'Drupal\\mysql\\Driver\\Database\\mysql', 'autoload' => 'core/modules/mysql/src/Driver/Database/mysql/', 'pdo' => [...], 'init_commands' => [...]]; protected $schema = class Drupal\mysql\Driver\Database\mysql\Schema { protected $connection = ...; protected $placeholder = 6; protected $defaultSchema = 'public'; protected $uniqueIdentifier = '01612a037ec15984a9a52b8f'; protected $mysqlStringTypes = [...] }; protected string $prefix = ''; protected array $tablePlaceholderReplacements = [0 => '"', 1 => '"']; protected $escapedTables = ['cache_container' => 'cache_container', 'cache_page' => 'cache_page', 'cache_config' => 'cache_config', 'config' => 'config', 'cache_discovery' => 'cache_discovery', 'cache_bootstrap' => 'cache_bootstrap', 'path_alias' => 'path_alias', 'cache_data' => 'cache_data', 'router' => 'router', 'cache_entity' => 'cache_entity', 'cache_routes' => 'cache_routes', 'magazine_paywall_anon_views' => 'magazine_paywall_anon_views', 'cache_dynamic_page_cache' => 'cache_dynamic_page_cache', 'cache_render' => 'cache_render', 'comment_field_data' => 'comment_field_data', 'cache_default' => 'cache_default', 'node_field_data' => 'node_field_data', 'node__field_articles' => 'node__field_articles', 'media' => 'media', 'media_field_data' => 'media_field_data', 'key_value' => 'key_value', 'cache_menu' => 'cache_menu', 'node_revision' => 'node_revision', 'users_data' => 'users_data', 'menu_tree' => 'menu_tree', 'cachetags' => 'cachetags']; protected $escapedFields = ['' => '', 'collection' => '"collection"', 'name' => '"name"', 'config.name' => '"config"."name"', 'base_table.status' => '"base_table"."status"', 'base_table.alias' => '"base_table"."alias"', 'base_table.langcode' => '"base_table"."langcode"', 'base_table.id' => '"base_table"."id"', 'base_table.path' => '"base_table"."path"', 'cid' => '"cid"', 'expire' => '"expire"', 'created' => '"created"', 'tags' => '"tags"', 'checksum' => '"checksum"', 'data' => '"data"', 'serialized' => '"serialized"', 'table_schema' => '"table_schema"', 'table_name' => '"table_name"', 'table_type' => '"table_type"', 'viewer_key' => '"viewer_key"', 'viewed' => '"viewed"', 'v.nid' => '"v"."nid"', 'v.viewed' => '"v"."viewed"', 'c.entity_id' => '"c"."entity_id"', 'c.entity_type' => '"c"."entity_type"', 'c.field_name' => '"c"."field_name"', 'c.default_langcode' => '"c"."default_langcode"', 'c.status' => '"c"."status"', 'c.cid' => '"c"."cid"', 'thread_order' => '"thread_order"', 'node_field_data.status' => '"node_field_data"."status"', 'node_field_data.created' => '"node_field_data"."created"', 'node_field_data.nid' => '"node_field_data"."nid"', 'node_field_data_created' => '"node_field_data_created"', 'bundle' => '"bundle"', 'uuid' => '"uuid"', 'prompt' => '"prompt"', 'operation_type' => '"operation_type"', 'provider' => '"provider"', 'model' => '"model"', 'output_text' => '"output_text"', 'configuration' => '"configuration"', 'extra_data' => '"extra_data"', 'tokens_input' => '"tokens_input"', 'tokens_output' => '"tokens_output"', 'tokens_total' => '"tokens_total"', 'tokens_reasoning' => '"tokens_reasoning"', 'tokens_cached' => '"tokens_cached"', 'response_text' => '"response_text"', 'entity_id' => '"entity_id"', 'revision_id' => '"revision_id"', 'delta' => '"delta"', 'langcode' => '"langcode"', 'tags_value' => '"tags_value"', 'base_table.uuid' => '"base_table"."uuid"', 'media_field_data.default_langcode' => '"media_field_data"."default_langcode"', 'base_table.vid' => '"base_table"."vid"', 'base_table.mid' => '"base_table"."mid"', 'nid' => '"nid"', 'n.created' => '"n"."created"', 'base_table.nid' => '"base_table"."nid"', 'subquery_base_table.nid' => '"subquery_base_table"."nid"', 'module' => '"module"', 'uid' => '"uid"', 'menu_name' => '"menu_name"', 'expanded' => '"expanded"', 'has_children' => '"has_children"', 'enabled' => '"enabled"', 'parent' => '"parent"', 'id' => '"id"', 'menu_tree.id' => '"menu_tree"."id"', 'tag' => '"tag"', 'type' => '"type"', 'message' => '"message"', 'variables' => '"variables"', 'severity' => '"severity"', 'link' => '"link"', 'location' => '"location"', 'referer' => '"referer"', 'hostname' => '"hostname"', 'timestamp' => '"timestamp"']; protected $escapedAliases = ['name' => '"name"', 'config' => '"config"', 'id' => '"id"', 'path' => '"path"', 'alias' => '"alias"', 'langcode' => '"langcode"', 'base_table' => '"base_table"', 'nid' => '"nid"', 'viewed' => '"viewed"', 'v' => '"v"', 'expression' => '"expression"', 'c' => '"c"', 'cid' => '"cid"', 'thread_order' => '"thread_order"', 'node_field_data_created' => '"node_field_data_created"', 'node_field_data' => '"node_field_data"', 'node__field_articles' => '"node__field_articles"', 'vid' => '"vid"', 'mid' => '"mid"', 'media_field_data' => '"media_field_data"', 'created' => '"created"', 'n' => '"n"', 'maximum_revision_id' => '"maximum_revision_id"', 'subquery_base_table' => '"subquery_base_table"', 'sq_base_table' => '"sq_base_table"', 'ud' => '"ud"', 'menu_tree' => '"menu_tree"', 'cachetags' => '"cachetags"']; protected $identifierQuotes = [0 => '"', 1 => '"']; private array ${Drupal\Core\Database\Connection}enabledEvents = []; protected Drupal\Core\Database\Transaction\TransactionManagerInterface $transactionManager = class Drupal\mysql\Driver\Database\mysql\TransactionManager { private ?string ${Drupal\Core\Database\Transaction\TransactionManagerBase}rootId = '16abc3ebbd40e88540d8b7b6'; private array ${Drupal\Core\Database\Transaction\TransactionManagerBase}stack = [...]; private array ${Drupal\Core\Database\Transaction\TransactionManagerBase}voidedItems = [...]; private array ${Drupal\Core\Database\Transaction\TransactionManagerBase}postTransactionCallbacks = [...]; private Drupal\Core\Database\Transaction\ClientConnectionTransactionState ${Drupal\Core\Database\Transaction\TransactionManagerBase}connectionTransactionState = enum Drupal\Core\Database\Transaction\ClientConnectionTransactionState::Committed; public bool $triggerWarningWhenUnpilingOnVoidTransaction = FALSE; protected readonly Drupal\Core\Database\Connection $connection = ... }; private $serverVersion = NULL }, $clientConnection = NULL, $query = 'SELECT "cid", "data", "created", "expire", "serialized", "tags", "checksum" FROM "cache_config" WHERE "cid" IN ( :cids__0 ) ORDER BY "cid"', $options = [], $rowCountEnabled = FALSE ).../Connection.php:441